Jabiru engine failures [Archive]

Mach E Avelli

13th Nov 2014, 04:43

Nail in the coffin indeed. It will destroy Jabiru's export market totally and devalue any Jabiru powered product here to the point where some of us will fly our aircraft until the first sign of an engine problem, then scrap it. I had already arrived at that conclusion. Others may just scrap it anyway, rather than live with the risk - whether real or imagined. Flying schools using the Jabiru product will go the way of the dodo.

It would be interesting to compare the failure rate of Jabiru engines here with that in the USA where they have been quite popular with home builders of Sonex and the like. Then compare with VW, Corvair, Subaru etc both here and in the USA. It may be that our Yank allies actually know something about the care and feeding of engines that we could learn.

Ultralights

13th Nov 2014, 05:40

im not sure if its operator error, as jabiru claim on every occasion, as there are 3 main failure modes.
Rotax engines are maintained by the same type of people, but have varied failure modes, and a majority are not related to the engine itself, but the accessories such as ignition modules, carbys etc.

to me, an obvious serious failure mode such as the through bolt failures to me suggest a design flaw. but sadly, IMO, jabiru seam to have their heads in the sand when searching for a solution. with no feedback to operators on the cause of a failure.
I have spoken to engineers that maintain jabirus, and have had no issues right to TBO, and they have described the reasons behind the failures, and yet, nothing is done to address the issue, No SB, no changes to maintenance manuals, nothing.

I think CASA is being a bit harsh with these restrictions, but when has CASA ever done anything to help improve aviation..... it would rather see loss of livelihoods, the demise of a local aircraft manufacturer and a large number of schools than try to resolve the issue and to improve the industry...

Eyrie

13th Nov 2014, 05:52

So does anyone know what the various failure modes are that CASA refers to?
What is the actual failure rate per 10,000 hours for these engines?
How does this compare to the failure rate of Rotax ( both 2 and 4 stroke) ?
Other engines used in similar aircraft? We don't yet have good numbers on the new Lycoming O-233 or the Continental O-200D I think as they are too new.
How many pilots/passengers/students/innocents on the ground have been killed or injured by these failures?
Until CASA put some numbers to these questions we are dealing with mere conjecture and "feelings".
I wonder where CASA are going to get any engineering expertise to investigate this? They are merely paper shufflers.
Oh and if in the near future I see another manufacturer/importer advertising a suitable replacement I won't be the least bit surprised, however this could completely wipe out small aircraft manufacturing in Australia. Wonder how Brumby Aircraft are feeling right now?
Any bets on what it will cost them to re-engine the already certified Aircruiser? Bet it is more than it cost to certify the whole aircraft even in inflation adjusted dollars.

Sunfish

13th Nov 2014, 06:52

CASA will probably go after Rotec radials next. Anything to kill Australian industry.

tecman

13th Nov 2014, 07:02

Part of the problem is that it's been scandalously difficult to get hold of good statistics and decent accident reports. I've previously banged on about the failings of RAA in that regard and suggested that if RAA weren't going to do the job, CASA must. Even my amateur spreadsheet compiled from the published gobbets indicates a serious problem and, as others say, resolving the problems would have been preferable to the seismic event we now have. But the fact is that the elephant in the room has been clearly visible, and something had to give.

In the end, it's not CASA's job to design or re-work engines but I hope they do take the opportunity to publish what information they have. At least then it might be possible to have an evidence-based re-work program, although I doubt it'll come from Jabiru based on past responsiveness. Whatever the source of the fix(es), I hope that the new RAA order buys into it to help the many poor sods who'll be affected.

Ultralights

13th Nov 2014, 07:04

Eyrie From the Raaus engine survey..
Typical engine types included in the response consisted of about one third Jabirus, one third Rotax 4 strokes (912/914) and the remainder comprising Lycoming, a large number of Rotax 2 stroke engines along with auto engine conversions such as VW and Subaru.

Interestingly, for ongoing discussions about the availability for MOGAS at airfields, over two thirds of respondents used MOGAS.

More than half the members completed their own maintenance and very encouragingly, the overwhelming majority of members adhered to the manufacturer maintenance schedule. Also encouraging was the vast majority of members reported completion of all Service Bulletins (SBs) and Airworthiness Directives (ADs) for the engine types.

And the failure part..
Almost one fifth of members who responded had suffered an engine failure, which may have been a trigger and motivation for them to complete the survey. Of these engine failures, just over half were as the result of a mechanical failure.

To summarise these failures, the majority of mechanical failures for Jabiru engines related to piston/ring, exhaust valve and through bolt failures, while Rotax issues included sprag clutch issues, CDI or electronic ignition failures and gearbox problems. General failures relative to all types include a large number of fuel or carburettor related issues including a surprising number of fuel contamination issues, electrical failures of various types including charging issues, cooling system issues and propeller issues.

Ultralights

13th Nov 2014, 07:11

Dont forget Jabiru sell a lot more engines to the USA, South Africa, and Europe... so, it might hurt, but wont be a killer..

Jabawocky

13th Nov 2014, 07:14

Removed because when a thread gets merged……and the post that I was correcting is removed it makes me look like a higher spec dill than I am capable of doing myself! :-)

:ugh:

Squawk7700

13th Nov 2014, 07:45

They are meeting with CASA tomorrow in Canberra at 11am with lawyers.

Brumby? The company manufacturing in China, that one?

Ultralights

13th Nov 2014, 08:04

they should be consulting with some decent engine engineers and solving the problem.

Sunfish

13th Nov 2014, 08:37

Too late! CASA Only needs to delay and Jabiru is toast and with it any other possible Australian engine start ups.

The mere threat of rule making will destroy sales.

This of course begs the question, asked already by others, of exactly what statistical data CASA is using to justify its position. I would assume a rock solid statistical case that demonstrates beyond doubt that the Jabiru engines are unacceptably unreliable.

I assume this is based on ATSB data...."oh wait! Do they investigate Jabiru incidents?"."...or is this the same as Pel Air? Reach the conclusion then construct the data that justifies it?

illusion

13th Nov 2014, 09:20

Empirical observational would suggest there is a serious problem with the engine concerned.
Would I send my wife, son or daughter on a scenic flight in a Jabiru powered craft.............???

NO, NO ,NO!!! (wife maybe in 20 years time....)

Would I as a 15,000+ hour pilot who has flown gliders and all things aeronautical own or operate one of these things????

NO!!! Flying is The art of managing risk, not playing Russian Roulette.

Since time immemorial , "ya get wot ya pay for"

What is most concerning is not the CASA response, but the lack of endeavour from the manufacturer to address glaring issues with the product.

While I am not a fan of these goverment d--kheads, perhaps this is the kick in the arse needed to get the Jabiru horse in motion.

allthecoolnamesarego

13th Nov 2014, 09:30

Can't please some people. When CASA does nothing, they whinge, when CASA acts, they whinge.

It seems like the Jabiru engine is not particularly reliable. It also seems from other discussions on Jabiru's, that there is little to no help FROM Jabiru.

If Jabiru fixed the problem with the engines, instead of putting their head in the sand, then maybe they would not be in this situation now.

I'm glad CASA have acted....finally.

andrewr

13th Nov 2014, 10:39

It would be interesting to see the statistics this is based on, and where Jabiru actually ranks in risk against other aircraft.

More, or less engine failure related deaths per hour than the Piper Navajo?
More, or less engine failure related deaths per hour than the piston engine fleet average?
More, or less engine failure related deaths per hour than from Robinson fuel tanks?

Interesting too that this comes so close to the implementation of the RPL, where CASA are basically offering RAA pilots equivalent licenses to fly GA aircraft.

What percentage of the RAA fleet has Jabiru engines? What percentage of the training fleet? If half your schools go broke because they can't send students solo for 6 months, and half your pilots switch to GA because they can't take a passenger in their Jabiru, it must endanger RAA in general. In that case, the cost of this could run into the hundreds of millions in failed businesses and loss of aircraft value.

I hope CASA have the (statistically significant) evidence to back it up.

triton140

13th Nov 2014, 10:49

Interesting too that this comes so close to the implementation of the RPL

I always thought the RPL was CAsA's Plan B, so that if they thought it was necessary (dodgy registration process, dodgy engines, dodgy training, dodgy whatever) they could shut RAAus down and shift everyone to GA RPL.

Looks like it might come to pass.

Bit of a puzzle though, the Jab engine - in our flying school the Jabs have done around 13,000 hours cumulative, and pretty much every engine has gone the full TBO despite all the crap that students can hand out. One engine failure over 7 years or so. And yet others the engine carks it after a few hundred hours.

Even so, would I buy one? Nope. Do I feel comfortable on a long flight? Not really.

Kharon

13th Nov 2014, 18:15

No doubt I will be corrected where wrong, but at face value seems to me CASA have acted responsibly and reasonably here. They are between a rock and a hard place; but they have not grounded the fleet and they are meeting and consulting with interested parties. I'd say that was a good thing and a positive move, when you consider the alternatives.

This appears to be one of those problems – similar to an intermittent fault – if the thing breaks, then the decision is easier, i.e. if all Jab donkeys quit, every time it's a no brainer. But it seems there are those engines which go to TBO and beyond and those which are much less obliging. Mach. E has provided a possible way forward and a good, potential bargaining chip:-
It would be interesting to compare the failure rate of Jabiru engines here with that in the USA where they have been quite popular with home builders of Sonex and the like. Then compare with VW, Corvair, Subaru etc both here and in the USA. It may be that our Yank allies actually know something about the care and feeding of engines that we could learn. And use....

CASA can't have the Jab fleet parked in paddocks and shopping malls around the country, but clearly they are prepared to discuss; and, by limiting the risks as they appear to have done, perhaps it's a sign. I reckon it's up to the manufacturer and perhaps the operators to show willing and prove to CASA that the product and operation can be made more reliable.

I can only hope this is the start of reformation and a non combative response from those affected can demonstrate that 'industry' is willing to cooperate in jointly achieving a sane, sensible solution – which would be a much better outcome.
tecman - In the end, it's not CASA's job to design or re-work engines but I hope they do take the opportunity to publish what information they have. At least then it might be possible to have an evidence-based re-work program,

Just saying

Jabawocky

13th Nov 2014, 20:07

Bit of a puzzle though, the Jab engine - in our flying school the Jabs have done around 13,000 hours cumulative, and pretty much every engine has gone the full TBO despite all the crap that students can hand out. One engine failure over 7 years or so. And yet others the engine carks it after a few hundred hours.

Indeed.

Bit of a puzzle though to understand it. I reckon I have half an idea about the various strengths and weaknesses both by design / manufacture and how they are operated/maintained.

The problem is I doubt the folk at CASA actually can comprehend it and work out what data means what. It will be a complex weave of data with hidden gems. Analysing the numbers (statistically) is one thing, but knowing how to weed out certain factors and weight them accordingly on this topic will be a headache.

Considering the number of movements and the number of recorded failures the failure rate is very low, but that is relying on accurate statistical data collection of course.

RAAus have published a response, part of it says this.
CASA has not previously notified RA-Aus of their intended actions, however, we acknowledge the engine failures associated with Jabiru power plants. It would appear the proposed actions by CASA are disproportionate to the risks faced by owners and operators. Of more than 90,000 Jabiru movements recorded by RA-Aus in the year to date approximately 0.03% have resulted in some form of engine malfunction with no fatalities being attributable to these events.

Jetjr

13th Nov 2014, 20:33

Could be a case of CASA pushing ahead with confronting restrictions BECAUSE other methods to fix the problem dont exist within their regulation. God forbid they would look into this probelm.

Most Jabirus are LSA, only way to be used in training.
They have NO way to implement any modifications without manufacturer approval. There simply is no process for outside upgrades to be made and retain LSA status.
Basically no STC process.

There are aftermarket improvements available and more coming however many owners cannot today or ever use them unless Jabiru approve it.

Its a bigger issue than just this engine, what happens when Euro company closes? No way to keep it in training use

This ham fisted approach is attempting to force a company to accept others work, assuming its for sale, and take reponsibility for it.

OZBUSDRIVER

13th Nov 2014, 20:38

Sounds like a metallurgical level issue.
If I was running Jab I would be offering good deals for engine swaps for engines that reach TBO. Would be smothering a few high use engines with data logging. The engineer in me sees these failed engines as very valuable resources...why the hell isn't the manufacturer doing deals to get the cores back into the factory and under the microscope.

Sunfish

13th Nov 2014, 21:23

Ozbusdriver:

Sounds like a metallurgical level issue.
If I was running Jab I would be offering good deals for engine swaps for engines that reach TBO. Would be smothering a few high use engines with data logging. The engineer in me sees these failed engines as very valuable resources...why the hell isn't the manufacturer doing deals to get the cores back into the factory and under the microscope.

Without a competent statistical analysis of the failure types and rates, CASA and the RAA are wasting their time.

However I doubt that a technical analysis of failure modes is going to be much help to the Jabiru engine company for the following reasons:

1. Statistical analysis may not prove conclusive given that ATSB does not investigate incidents and the RAA seems to be wanting as well. There also needs to be a distinction drawn between what I will call "professionally maintained" engines and amateur maintenance of kit built aircraft. This needs to be done so that conclusions can be drawn about different fleets because failure may be maintenance sensitive (or not). Then there is the question of mod status.

2. Now that Lawyers are involved (if its CASA, the lawyers are calling the shots) Jabiru faces an almost insuperable barrier to a return to normal operations because it is going to be asked to present "negative Evidence" ie: Evidence that demonstrates that the engine is safe by industry standards. That involves identification of failure mode, corrective action then considerable testing to prove that the problem is fixed at the 99.999 percent confidence level.

However even this won't be enough. Now that CASA has got itself involved it has foregone the defence of "plausible deniability" if there is a multiple fatality. What will now be required of Jabiru is an impossibly high standard of evidence such as to be sufficient for a court to completely exonerate CASA from all liability whatsoever in the event of a future accident. I do not believe CASAs lawyers will settle for anything less and I think they will take their time before deciding.

I short-handed this message in an earlier post but my feeling is that I doubt the Jabiru cash flow can sustain such a marathon nor will engine sales continue while it is in this state.

If its any consolation at least CASA didn't wait till Friday at 4.30pm.

P.S. To be fair to CASA, I believe I've heard that Jabiru management has been somewhat less than proactive in the product improvement area, but I stand to be corrected.

thorn bird

13th Nov 2014, 22:08

Oh well, I am sure there is a Chinese company willing to buy up the design.

Cheap!

Without "Foster and Promote" in their charter there is no incentive for CAsA to work "with" anyone except the lawyers who's only brief is liability "risk management", forget about safety.

Industry has safety risk management programs.

CAsA has a Liability risk management programs.

Its easy to be critical of the company, but CAsA at times, especially if your confronted by the wrong person, can be impossible to deal with.

Its not just CAsA unfortunately the liability risk management model is infused right across the bureaucracy, which is partly why we don't make anything here anymore.

triton140

13th Nov 2014, 22:10

Jaba, with your experience, do you think this can be fixed quickly?

Seems like the major problems are still the through bolts (?rolled vs cut threads), valve guides (?cam/rocker design) and crankcase fretting. Of course, as Sunfish points out, we don't have any good stats and there is the maintenance confounder, but do we have the answer and is it as simple as an SB (I suspect not, but we can live in hope).

Pity Jabiru has chosen to head to Canberra with their lawyers instead of engineers. They have received poor PR advice - the legal approach and a letter writing campaign will not wash with CASA (or more importantly the public, ever fearful of those nasty ultralights crashing through the roof of their kindergarten), it just looks like a defensive cover up. Over many years, and across many industries, we have learnt that the only way to deal with these crises is to fess up and be cooperative in working to find a solution. The lawyers will only stuff it up and hasten the demise of Jabiru - we need experts here, not guns for hire.

There are times I hate CASA with a passion, but I have to agree with Kharon that it seems they had little option - Jabiru has failed to deal with the known issues and RAAus has failed in its responsibilities (I think after all the fiascos, CASA will give them trikes not above 300ft and roll everything else back into CASA/RPL and who could blame them).

Squawk7700

13th Nov 2014, 22:11

You are not wrong JetJr.

LSA is a can of worms for aircraft manufacturers and owners.

If any one of these European aircraft manufacturers goes belly-up, then Aussie private operators and flying schools have 30 days before their birds are grounded and then transferred to experimental registration, thus rendering their flying school and income potential zero, or at least until they can get another aircraft on-line.

If Jabiru went under, the majority of schools with Jabiru aircraft are gone in 30 days.

I'm thinking though and I know it's different..... Cessna stopped making aircraft and General Aviation didn't cease across the world.

triton140

13th Nov 2014, 22:14

If its any consolation at least CASA didn't wait till Friday at 4.30pm.

Given responses due Thursday 20th, expect the final instrument to be faxed 4:30pm on Friday 21st ....:E

OZBUSDRIVER

13th Nov 2014, 22:23

Sunnie, me think there are too few...as many as there are worldwide...for a stat method to pick up faults. The best way is to get your hands dirty and start reading the witness marks and recording individual events to make the picture from that end rather than failure o'er 100000hrs in use. The company is small run so it should never have been difficult to change a design, process or material.

motzartmerv

13th Nov 2014, 22:53

Sad turn of events, for Jab and the RAA. Makes us all look like a pack if diks really. I hope Jab come to the party and initiate real change, and I hope CASA can relax their grip around the throats of Jab and allow it to happen. Knowing the company tho, I dont hold much hope for compromise.

Squawk7700

13th Nov 2014, 22:58

Both parties meet in a few minutes at 11am.

Let us hope for an outcome that keeps everyone happy.

RA-Aus is meeting with CASA today also.

Dexta

13th Nov 2014, 23:11

Having been on the pointy end of a Jabiru engine failure, having completed the Jabiru Maintenance Course and having run a flying school which used a Jabiru I have a few insights into the issue.
Firstly you need to differentiate between the 2200 & the 3300, each engine has it's own but different problems. The 2200 is mainly through bolts and the 3300 is mainly pistons/rings and especially exhaust valves. Secondly you have to differentiate geographically if the engines are run on AVGAS. The West, including SA (and maybe NT) are supplied with the Green, high lead, fuel while the East is generally supplied with the low lead blue. This has an impact on lead build-up in the engine.
Thirdly you need to differentiate on equipment level, i.e. do they have the single CHT sensor on No. 6 or are they fitted with the Dynon and have EGT/CHT on all cylinders.
With regards to maintenance it is no so much wether it was a "Professional" or an "Amateur" but more a case of how often. For example, a J230 (3300 engine, running on AVGAS Green with single CHT) has a top end clean (deposits removed, valves lapped etc) every 200 hours and hasn't had a failure in over 600 hours. This is not part of the Jabiru recommended maintenance schedule. The point being some people will go above and beyond the "required/scheduled" maintenance or strip the engine/top end at the slightest possibility of a hint of a problem. When this engine goes to TBO they say they never had a problem or failure, which is true. The other person who just does the recommended scheduled maintenance per the book, to Jabiru standards, plus any AD's etc and the engine fails at 300+ hours whilst flying therefor generating a statistic.
Most of my experience is with the 3300, and the engine will go to TBO IF you clean the top end every 200 hours, modify the baffling to get an even spread of CHT's (illegal if 24 reg) and fit fuel injection (again illegal) or possibly re-jet to run really rich (25-30 L/hour at 75% power).
As for the 2200 engines I'm not sure, but one here is only used for private flying and generally flies at 2900-3000 rpm, doesn't do circuits, is maintained above and beyond recommended levels and is running nice at 400+ hours so far.
In my case the engine was maintained to the required level as per the Jabiru Maintenance Manual, only had the single CHT and run on green AVGAS. After doing the mandatory morning pull throughs with no issues, at 282 hours about 40 minutes into a 2 hour flight the engine ran rough for 10 seconds then stopped solid, found a paddock and got down with only a few bruises. Aircraft carted off to Jabiru by the insurance company, and when we tried to find out what went wrong with the engine they wouldn't tell us! When we asked for the engine to be sent back they said they can't because it had been binned! We got a new engine (we got pro-rata for the hours remaining) and our aircraft fixed but to this day have no concrete evidence of what happened.

motzartmerv

13th Nov 2014, 23:38

And there is the problem Dexta. My school has had similar stories.

fujii

14th Nov 2014, 00:05

https://www.facebook.com/JabiruAircraft?fref=ts

The problem also appears in the Private Flying forum.

pilotdaz

14th Nov 2014, 00:11

Sign the petition (https://www.change.org/p/the-hon-warren-truss-mp-cancel-casa-s-proposed-restrictions-on-jabiru-aircraft-engines?recruiter=104285760&utm_source=share_petition&utm_medium=email&utm_campaign=share_email_responsive) at CHANGE.ORG (https://www.change.org/p/the-hon-warren-truss-mp-cancel-casa-s-proposed-restrictions-on-jabiru-aircraft-engines?recruiter=104285760&utm_source=share_petition&utm_medium=email&utm_campaign=share_email_responsive) if you can.
Results will be forwarded to Warren Truss MP.

There appears to be overwhelming support from the aviation community that CASA is being too heavy handed here.

poteroo

14th Nov 2014, 02:04

After 4 yrs of persistence, in 2013 we finally gave up on our J160 which had done 850TT for 2 engines and loads of grief in between. We were unable to rely on the aircraft, and lost sleep over student flying. We were most unhappy with the manufacturers attitude.

We sold it for a very acceptable price in late 2013. We've ordered a Brumby and take delivery soon.

So, todays crunch was a long time coming!

Jabawocky

14th Nov 2014, 02:05

This is where a lot of the problems could be fixed.
modify the baffling to get an even spread of CHT's (illegal if 24 reg) and fit fuel injection (again illegal) or possibly re-jet to run really rich (25-30 L/hour at 75% power).

The cooling air distribution is something very few understand at all.

Fuel DOES NOT COOL, it delays the Theta PP and lowers the ICP. Hence a lower CHT. This is the wrong way to cool an engine.

I reckon cooling issues and distortion of heads as a result are 45% of the problems, and the result from running far too rich the other 45%. 10% could be any number of things. Just shooting from the hip.

Squawk7700

14th Nov 2014, 02:45

Fuel DOES NOT COOL, it delays the Theta PP and lowers the ICP. Hence a lower CHT. This is the wrong way to cool an engine.

Agree with Jabba on this one 100%.

Jabiru engines in their native installations run hot.

Many an owner / maintainer simply pumps in additional fuel in an attempt to "cool" the engine. It will take a lot of fuel to cool a cylinder; in fact you may cool the head but not the cylinder. In fact by pumping in extra fuel you run the risk of it going through in gobs and causing issues; this is an issue in aicraft that are un-cowled.

AIRFLOW is the only way to cool these AIR COOLED engines. Unless you are running a stupidly lean mixture and cooking your heads, adding fuel will NOT help.

A 120hp Jab engine should in theory be able to run at around 19 lph IF cooled properly with AIR.

I can definitively demonstrate to anyone that wants to watch, that fuel will NOT cool a Jabiru engine or at least not to any significant amount worth mentioning.

If owners weren't skimping on engine monitoring and took the time to listen to the factory and fit 8 or 12 senders for CHT & EGT and take notice of what they are telling them, then a significant proportion of these issues would have been nipped in the bud a long time ago.

There are owners at my airport too stingy to fit the required instrumentation and thus are hitting regular problems like valves burning out. At least with monitoring, mixtures could be adjusted accordingly to rectify the problem. Some would say that an owner shouldn't have to do this, however if you have the ability to fit such devices and rectify the problems, you would be crazy not to.

Ultralights

14th Nov 2014, 02:57

from talking to other LAMEs who have had a good record with Jabirus, it could possibly be the construction technique that is the root cause, and also, not having any idea whats going on with regards to mixtures and combustion events.

the crank cased are bolted together, no gaskets, just metal to metal and a thin layer of silicon between the mating surfaces.. something i have been told is a big no no in engine construction... leads to fretting etc...

Unless you are running a stupidly lean mixture and cooking your heads
Don't you mean, Not lean Enough?

Squawk7700

14th Nov 2014, 03:09

Yes Mr APS attendee. You know what I mean, stupidly lean.

Out of balance props certainly contribute to fretting.

There is now fretting across the entire Jabiru fleet, but fretting of a different kind.

Jabawocky

14th Nov 2014, 03:32

Yep, a simple Bendix or Airflow performance style injection system. I reckon it could have two settings, and being mass airflow designs they could have a F/A ratio set for take off and climb, and one for cruise and descent.

Piece of cake with the right motivation. That and proper cooling, or even the Rotec water cooled heads. which would mitigate that issue. Although I prefer a proper air cooled design, it works well for Rotax and seems to work for others.

Along with some material changes on valve guides and we would solve most issues easily. I am not sure the hydraulic lifters are the go, and with the old solid lifter engines (less problems) and better F/A ratio's and cooling, most of the head creep would go away.

I see a solution…..if only we can get them to have me around the table. If anyone is reading this that matters.

Andy_RR

14th Nov 2014, 03:56

I wonder if there's more to this than meets the eye. Jabiru don't actually manufacture these engines and I've heard that the guy who does has been concerned about the design being shipped elsewhere.

I have no concrete evidence - this is a rumor network after all - but there could be some inter-company politics behind this that has gone wrong, or right or something else entirely.

I feel for the guys making the Jab engine because they do know how to make them and they have a much better reputation overseas than they do here (sound familiar...?) It's also an industry with high costs and slim margins where redesign and re - certification is often prohibitive, let alone new designs.

It's something of a shame that CASA didn't knock on the door and have a quiet word to fix this up without destroying company and brand reputations, but perhaps they already have tried this and failed so they turned to the nuclear option. I don't know.

Whatever happens, it's always easier to destroy than it is to build up and plenty of Aussies seem to like to see destruction...

Andy_RR

14th Nov 2014, 04:03

It's also interesting and slightly disturbing that the consultation draft published doesn't list any engine types, model numbers or failure modes.

In my opinion, that's pretty poor professionalism on CASA's part. Why has the failure rate on an unspecified series of engine models suddenly become "an urgent safety risk"?

It would be easy to construe this as a commercial vendetta on someones part rather than a valid safety action.

Arnold E

14th Nov 2014, 04:06

it's always easier to destroy than it is to build up and plenty of Aussies seem to like to see destruction...

Witness our government, for instance.:{

Squawk7700

14th Nov 2014, 04:09

Absolutely Andy. How about some serial numbers, 4 or 6 cylinders, thru bolt compliance, etc. Nothing at all from them as yet.

andrewr

14th Nov 2014, 04:41

Fuel DOES NOT COOL

Would you care to elaborate on that?

Formation of CO2 releases more than 3x the energy of CO.

My high school chemistry calculations (admittedly with 25+ years of rust) suggest that 10% excess fuel reduces the energy (heat) released by about 3%.

You get more molecules and hence more pressure at the same temperature, or the same pressure at a lower temperature.

Ndegi

14th Nov 2014, 04:51

Andy RR, I think that you will find CASA have had a couple of Audits of the Bundaberg factory where the topic was raised.

Also worth a look at the Jabiru Facebook page to see the owner reaction for and against the CASA proposal.

Andy_RR

14th Nov 2014, 05:16

Ndegi, that may be true, but the CASA proposal makes no concrete case for the action. It's all hearsay and anecdote and, like I said, no data, serial numbers, model numbers or anything.

All engines have their weak points which need to be managed, but CASA wouldn't dare put blanket restrictions on "Lycoming engines" or "Continental engines" without specifying models, build dates, specs, installations or some other form of identification. Why is it OK to do this to a local manufacturer?

Even if Rod is being blind or belligerent, it's not CASA's job to "teach him a lesson" by wielding a big regulatory stick without just cause.

Draggertail

14th Nov 2014, 05:42

It's still just a proposal. Perhaps if the manufacturer supplies relevant data to limit the action to certain models or serial numbers CASA will change the proposal.

triton140

14th Nov 2014, 06:26

From today's RAAus email:

Reported data for 2014 year to date (January through October)

Hours flown
Jabiru 41,834
Rotax 71,626
All 131,227

Landings
Jabiru 92,735
Rotax 145,638
All 260,383

Engine failures (full or partial)
Jabiru 28
Rotax 16
All 51

That makes Jabiru 0.67 per thousand hours, Rotax 0.22 and others 0.39.

Jabs way in front, if the stats are complete (which they may not be, based on track record). Even if they aren't, it's a wide margin.

andrewr

14th Nov 2014, 07:03

I think you used landings for Rotax and hours for Jabiru. Rotax should be 0.22.

Draggertail

14th Nov 2014, 07:03

I make it Jabiru 0.67 per thousand hours, Rotax 0.22 and others 0.39.

Jabiru 3 times more likely to fail than Rotax.

Jabiru almost twice as likely to fail as the "others".

Enough reason to take action I suppose but I wonder why these stats are only now coming out. Why haven't RAAus (or CASA) advised us of this before. If they had then maybe market forces would have forced Jabiru to take action.

triton140

14th Nov 2014, 07:04

I think you used landings for Rotax and hours for Jabiru. Rotax should be 0.22.

Indeed - fixed, thanks!

waren9

14th Nov 2014, 07:07

are rotax's more likely to be in installations where engine failures are shall we say less likely to be reported?

Andy_RR

14th Nov 2014, 07:24

It's interesting data, but not really very enlightening.

Rotax = 447, 582, 912A/F/S/iS/UL/ULS 914F/UL and probably other variants

Jabiru = 2200 and 3300

Others = ?

Of course installation plays a big part in reliability too, so how many variations do all these account for?

Looking at the data from flight hours/landing perspective, you have 0.45hrs for Jabiru, 0.49hrs for Rotax and 0.50hrs as a fleet average, so clearly the use profile for Jabirus are different from Rotaxes and just what is it that's bumping the fleet average beyond even that...?

The data might be enough to trigger an investigation, but enough to destroy a company's reputation in public by regulatory sabre rattling?

There's certainly a case for more information required before proposing a case for regulatory action. And this proposed action? Just what comment should the public make without any concrete data or information?

Draggertail

14th Nov 2014, 07:28

waren9, are you suggesting Rotax owners are more dishonest than Jabiru owners?

rutan around

14th Nov 2014, 07:50

waren9, are you suggesting Rotax owners are more dishonest than Jabiru owners? 14th Nov 2014 18:24

I don't know about 'Dishonest' but I thought with the 2 stroke engines failures were more or less ops normal. I know of a couple that I'd bet good money never landed on any report.

Squawk7700

14th Nov 2014, 07:59

It may just be all over after today's meeting with CASA.

There is work to be done and it's possible it may never come to fruition.

Draggertail

14th Nov 2014, 08:00

Rutan around, some at CASA seem to think a Jabiru engine failure is "ops normal".

Eyrie

14th Nov 2014, 08:17

Didn't Lee Ungerman work for RAAus? This issue hasn't suddenly arisen. Where was he then and what was he doing?

Duck Pilot

14th Nov 2014, 09:57

I would not put my wife in kids in an aircraft with a Jab engine, even with me driving it. Sad to see this happen to an Australian aircraft manufacture. In this case I believe CASA do have a legitimate reason to think about placing restrictions on the engines until the manufacture can come up with a suitable fix, which I doubt will happen unfortunately. Forget the stats, there is way to much evidence to convince me that the engines are unreliable, and I'm certain that there is a heap more engine malfunction events that haven't been reported.

Jabawocky

14th Nov 2014, 10:01

andrewr, answers inserted in red.
Would you care to elaborate on that? I did already, you just failed to copy and paste the rest of the answer.

Formation of CO2 releases more than 3x the energy of CO. OK, and by running richer and richer you generate a lot more CO. This was graphed way back before computers…I have the graph. I can't easily print the graph I know to be accurate but this one is probably near enough
http://www.crypton.co.za/Tto%20know/Emissions/airfuelratio5big.GIF

My high school chemistry calculations (admittedly with 25+ years of rust) Don't worry….I am worse off :sad:suggest that 10% excess fuel reduces the energy (heat) released by about 3%.

Not really, it slows down the burn rate, and the peak pressure occurs later, therefore at a lower peak pressure. Just like your air compressor, compress to a lower pressure you don't get the heads as hot. And no fuel used at al.

You get more molecules and hence more pressure at the same temperature, or the same pressure at a lower temperature. :confused:

LeadSled

14th Nov 2014, 13:09

Where was he then and what was he doing? Folks,
That is a very good question, I wonder when all the claimed shortcomings at RAA happened -- in the short time between him quitting and turning up at CASA, or on his watch.

The RAA has been much criticized, some of it justified, but much of the problems over certification of certain aircraft is a result of CASA changing the rules of the game, after the game is over, with a number of historic certification agreements being ignored, and effectively aircraft judged by current rules. That is a bit of an over simplification, but you get the drift.

If you did that (demanded compliance with current certification rules) to GA aircraft, it would ground most of the fleet. Only the GA 8 and a few recent types would survive. The great majority of Cessna, Piper and Beech would disappear from the skies.

Tootle pip!!

Stanwell

14th Nov 2014, 15:03

Jaba,
As an 'innocent bystander' these days, I cant help wondering why these issues have not been adequately addressed up to this point.

I, myself, have declined invitations to fly behind one of those apparently beautifully engineered powerplants.

Who stuffed up? How? Why?

Squawk7700

14th Nov 2014, 19:42

Stanwell, I would say 80% of the issues are quality control. It's one crisis to the next. Valves, rockers, collets, what is next? CASA are addressing this with them.

The other thing is the owners complying with the SB's.

When your LAME services your Cessna and you get $11,000 of sticker shock, you have no option but to pay it.

On the other hand, what is compelling you to upgrade the thru bolts on your owner maintained Jab? God, I've known of people that don't even have an engine or airframe log book! (Being careful with my words there)

Mach E Avelli

14th Nov 2014, 20:17

My experience with Jabiru the factory and Jabiru the engine is mixed.
The factory do not want to know you if you purchase second hand, and even less so if their engine is not installed in one of their Tupperware airframes. I emailed them with details of engine serial number, to ask if they had any records of its modification status when it left the factory, and to ask whether it had the 1000 hour TBO or the later, higher TBO. Not even a simple reply to say they had no knowledge of where it went after it got shipped out in a box, but based on serial number it would be a 1000 hour TBO.

The engine, a 2200 serial number 65 is one of their first of that series. So far, so good. The only issues have been a badly cracked muffler due to poor welding and some ignition faults which I fixed by replacing both rotors, both distributor caps and all the HT leads. It is owner maintained on the basis of if it ain't broke I don't fix it. The usual regular oil and spark plug changes and and a good look around for leaks and cracks and monitoring of compressions and tappet clearances is all. I imagine that swinging a wrench on through bolts etc would do more to break them than never touching them.

If this was the automotive industry, with 10,000 units on the road, the authorities would require a general recall to have the safety issues rectified at factory expense. But, hey, this is aviation and it's easier for the authority in this case to simply shut the factory. For those of us stuck with the product, if we can't have empty skies, solo skies are the next best thing.

Neville Nobody

14th Nov 2014, 20:30

Is t true the V6 Commodore pistons in Jabs are mounted with the gudgen offset opposite to normal practice?

Mach E Avelli

14th Nov 2014, 20:48

Apparently there was a batch of engines where they got it the wrong way around and therefore some failures and other cylinder damage resulted. Don't know when this happened or any other details.
If true, it reflects very poorly on their training and QA and certainly should have been a general recall with free fix.

Jabawocky

14th Nov 2014, 21:01

There was a cir clip problem about 2 years back I think that was gudgeon pin related.

The piston is based on the old V6 Holden engine piston and is manufactured at the same factory where ACL makes all their pistons. There are a few machining differences, the cir clip grooves, and a wider ring groove.

Stanwell…….I really can't answer your question I am not involved enough, just have a lot of exposure through various avenues.

poteroo

15th Nov 2014, 03:08

Is t true the V6 Commodore pistons in Jabs are mounted with the gudgen offset opposite to normal practice?

Keep digging in this area. Check out the reason South Africa reportedly gets such good performance out of their engines

Eddie Dean

15th Nov 2014, 03:50

More info and petition to minister here
https://www.change.org/p/the-hon-warren-truss-mp-cancel-casa-s-proposed-restrictions-on-jabiru-aircraft-engines

Squawk7700

15th Nov 2014, 04:17

There is a complex discussion paper on the Jabiru website regarding the piston installation. If you can read and understand it, your questions will be answered. Unfortunately I lost interest half way thorough because the end result didn't affect me.

abgd

15th Nov 2014, 06:06

Jabs way in front, if the stats are complete (which they may not be, based on track record). Even if they aren't, it's a wide margin.

Statistically significant for what it's worth - p<0.001 using chi^2

mnehpets

15th Nov 2014, 06:59

Looking at the most recent ATSB stats report (AR-2013-084), we can get a guestimate of the engine failure rate for GA by adding the accident, serious incident and incident counts for "powerplant/propulsion", and diving by the total hours. For 2012, we get a GA engine failure rate of 0.16 failures per thousand hours. Note that this includes single and multi engined aircraft, and both piston and turbine, so it's not exactly comparable to the jab/rotax numbers given by raa. Also, there's probably differences in counting engine failures vs prop failures.

There are RAA numbers in the same stats report, but those numbers look seriously suspicious.

While on the ATSB website, there's an open investigation by them into "light sport" engines (AR-2013-107). It was due to be released last month, but that has yet to happen. Perhaps that report has triggered CASA's action.

- S

triton140

17th Nov 2014, 05:50

Consultation period extended by 7 days. (http://www.casa.gov.au/wcmswr/_assets/main/newrules/download/cd1425ss-clarification-extension-consultation-period.pdf)

Lots of legal weasel words, not much substance - what happens when you get lawyers involved.

andrewr

17th Nov 2014, 06:26

Would you care to elaborate on that? I did already, you just failed to copy and paste the rest of the answer.

Formation of CO2 releases more than 3x the energy of CO. OK, and by running richer and richer you generate a lot more CO.

The rest of the answer didn't say anything about the amount of energy released.

When rich by definition you are limited by the amount of O2. If you produce CO instead of CO2, you can only get 2 x CO for every CO2. Not "lots" - exactly 2.

2 x 1/3 = 2/3, which is less than 1. For each 2 CO you produce, you lose about 1/3 the energy you would get if it was less rich and the O2 ended up as CO2.

My high school chemistry calculations (admittedly with 25+ years of rust) Don't worry….I am worse off :sad:suggest that 10% excess fuel reduces the energy (heat) released by about 3%.

Not really, it slows down the burn rate, and the peak pressure occurs later, therefore at a lower peak pressure.

Yes, really. The energy (heat) released is well documented. More CO = less heat.

The chemistry says less energy is released.
By definition, EGT is lower when richer than peak EGT.
Full rich generally gives lower CHT.

So I don't understand the claim that fuel doesn't cool. If richer mixture doesn't cool, where does the heat go with all these cooler temperatures?

Maybe "fuel doesn't cool, it just heats less"? Of course it may not be the most efficient way of cooling, but it doesn't mean the effect doesn't exist.

Creampuff

17th Nov 2014, 08:52

By definition, EGT is lower when richer than peak EGT.By definition, EGT is also lower when leaner than peak EGT.Full rich generally gives lower CHT.Full lean always gives lower CHT. Any mixture that's leaner than about 50 degrees F ROP will also give a lower CHT than at 50 degrees ROP.

So, taking away fuel can also cool, and adding fuel can also heat, depending on where you are on the lean curve before you start taking the fuel away or adding the fuel.So I don't understand the claim that fuel doesn't cool. If richer mixture doesn't cool, where does the heat go with all these cooler temperatures?If you start at peak EGT, and add fuel (make the mixture richer) so that the EGT goes down by about 50 degrees F, your CHT will go up. So in this example, adding fuel doesn't cool.

If you start at 50 degrees F lean of peak, and add fuel (make the mixture richer) so that the EGT peaks and then goes down 50 degrees F on the rich side of peak, your CHT will go up. Lots. So in this example, adding fuel still doesn't cool.

Making your mixture increasingly rich from around 50 degrees F ROP will result in lowering of CHTs, because all other things being constant, as the mixture is made richer from around 50 degrees F ROP the peak pressure point in the combustion cycle becomes later, and therefore the peak pressure becomes lower. (Using a higher RPM will help as well.)

Jabawocky

17th Nov 2014, 10:19

andrewr

if you have an engine at peak EGT and you make it richer, which by your example means it will get cooler, why then does it get hotter (CHT) when the EGT is falling? And once past about 50 or so dF CHT will drop again.

When you get the concept here, the rest of my answer will make sense.

Not trying to be a smart ass, just want you to challenge the thought processes. :ok:

Creamie is onto it.

Hempy

17th Nov 2014, 10:28

shhh. yr rihgt will be here in a minute!

yr right

17th Nov 2014, 21:21

Why dose cht rise. Because the energy is being released into the Cylinder chamber and not out the exhaust. Hence that's why you don't get burnt exhaust valves when running rop. But then again what would I know !!!

Creampuff

17th Nov 2014, 21:33

But then again what would I know !!!Right on cue! :D

You’ve demonstrated, time and time again, that you don’t know much about how engines run. That’s because you’re a piano tuner, not a piano player.

I can prove it.

Try this quick quiz, yr right.

(1) When will CHT be higher:
(a) When the mixture is leaned to peak EGT?
(b) When the mixture is leaned to 50 degrees F rich of peak EGT?

(2) How does a pilot know when the engine is running ROP?

The answers should be short and sweet, for someone of your enormous experience and knowlege. :ok:

andrewr

17th Nov 2014, 22:01

if you have an engine at peak EGT and you make it richer, which by your example means it will get cooler, why then does it get hotter (CHT) when the EGT is falling? And once past about 50 or so dF CHT will drop again.

The total energy released reduces as you produce CO instead of CO2. Total energy is divided between turning the prop (power), heating the engine (CHT) and out the exhaust (EGT).

CHT can increase while total energy decreases if there is a reduction somewhere else e.g. power or EGT. As you said, keep adding fuel and CHT drops too. No-one said that all temperatures had to drop in synchronization.

You can't create or destroy energy. The peak pressure point is a furphy - it cannot change the amount of energy you have, just where it ends up. If the peak pressure is later and CHT goes down, it means more energy goes out the exhaust or (possibly) turning the prop instead of heating the engine.

Adding fuel when you are limited by O2 (rich) means that the amount of energy released is reduced. Listing other factors that also result in a cooler engine doesn't change this fact. I'm not arguing with those factors - just the proposition that fuel doesn't cool. It does, unless you are LOP.

Lean mixtures causing detonation is something that has been documented for a long time in many different engine types. Maybe George Braly has shown that Continentals/Lycomings have enough detonation margin to run LOP without detonation. (You might however ask the question whether that margin belongs to the engineer or is the end user's to use.) That doesn't mean that every engine has the same margins.

I somehow doubt that he has done extensive testing of Jabiru engines and their detonation margins. Without that testing, suggesting that Jabiru engines would be more reliable if they ran leaner is dangerous guesswork.

The thing that worries me about this whole LOP thing is the number of pilots who think that every engine can be run LOP without danger, and that LOP is the answer to all engine problems. There is too much evidence to the contrary for me to believe that.

Andy_RR

17th Nov 2014, 22:12

andrewr, you have to remember that heat transfer is a function of temperature and temperature in a piston engine is a function of pressure, so you can dramatically shift the heat energy flow by raising and lowering the pressure by shifting the Pmax point with ignition angle or burn rate.

On an aero engine, ignition angle is fixed. The ignition delay is variable with air-fuel ratio as is the burn rate, so air-fuel ratio will have a large influence on the magnitude of and angle at which Pmax occurs, which in turn influences whether the heat goes to the cylinder head, makes mechanical work or heads out of the exhaust.

Oh, and exhaust valves burn when they leak. That's pretty much the only way you will overheat them without melting the cylinder head at the same time.

Creampuff

17th Nov 2014, 22:44

I'm not arguing with those factors - just the proposition that fuel doesn't cool. It does, unless you are LOP.What if you are at peak EGT and you add fuel until the EGT is 50 degrees F rich of peak? The thing that worries me about this whole LOP thing is the number of pilots who think that every engine can be run LOP without danger, and that LOP is the answer to all engine problems. There is too much evidence to the contrary for me to believe that.’Evidence’ eh?

So, it follows from that 'evidence' that to avoid those dangers and problems, you run your engine ROP.

How do you know your engine is running ROP?

This is what I find perpetually hilarious about these folklore-driven discussions. Let’s assume it’s cookd clys all the way and your wings will drop off if you don’t operate ROP.

How do you know your engine is running ROP?

Andy_RR

17th Nov 2014, 22:50

Adding fuel when you are limited by O2 (rich) means that the amount of energy released is reduced. Listing other factors that also result in a cooler engine doesn't change this fact. I'm not arguing with those factors - just the proposition that fuel doesn't cool. It does, unless you are LOP.

Just re-read your post and must comment on this. You might think it's semantics, but cooling refers to dumping waste heat to the environment. Running rich is not chemically generating the heat in the first place, so to call it cooling is disingenuous.

Sure, it runs cooler, but it isn't cooling any more than reducing the power level is cooling.

Creampuff

17th Nov 2014, 22:57

Exactly. Also demonstrated by the fact that you make the engine cooler by making the mixture leaner. :ok:

andrewr

17th Nov 2014, 23:01

You might think it's semantics, but cooling refers to dumping waste heat to the environment. Running rich is not chemically generating the heat in the first place, so to call it cooling is disingenuous.

Sure, it runs cooler, but it isn't cooling any more than reducing the power level is cooling.

See my post #74:
Maybe "fuel doesn't cool, it just heats less"?

So yes I agree, in part. But you could also say that cooling is "lowering the temperature" i.e. making it cooler. If you are trying to reduce your engine temperature you may not care.

Creampuff

17th Nov 2014, 23:05

So you're going to run your engine ROP to avoid the dangers and problems of LOP. Great.

How will you know your engine is running ROP?

Andy_RR

17th Nov 2014, 23:14

See my post #74:
Maybe "fuel doesn't cool, it just heats less"?

So yes I agree, in part. But you could also say that cooling is "lowering the temperature" i.e. making it cooler. If you are trying to reduce your engine temperature you may not care.

But the objective is not to cool the engine. It's to produce sufficient power without overheating the engine and its components.

andrewr

18th Nov 2014, 01:37

But the objective is not to cool the engine.

My objective is just to understand the statement "FUEL DOES NOT COOL" when the chemistry says otherwise.

Mach E Avelli

18th Nov 2014, 01:48

Thread drift! The whole LOP/ROP debate was done elsewhere only a month or so back.
I am completely sold on the benefits of LOP, and was when I did my DC 3 ground school nearly 50 years ago.
But this is about Jabiru engines. How can we run a standard Bing carburettor LOP? My understanding is you get whatever it thinks you need, and that will usually be well rich of peak.
Jabiru did try some lean burn jetting for a while, but I believe that it was too imprecise and caused more problems than it was worth.

The only way I could see to run a Jabiru LOP would be to get rid of the standard Bing set up and perhaps fit a Rotec. I would be grateful to hear from anyone who has done this and how has it worked out?

Wallsofchina

18th Nov 2014, 01:49

"Sure, it runs cooler", but it isn't cooling any more than reducing the power level is cooling.

Those four words are vital for someone running a little engine with a little carby with mixture controlled by the main jet, less piston clearance than the engine which originated the piston, a "lean" jet setting, and a "continuous loading" application.

Mach E Avelli

18th Nov 2014, 01:55

Walls, as the redhead once famously said "Please exPLAIN?."

andrewr

18th Nov 2014, 01:57

So you're going to run your engine ROP to avoid the dangers and problems of LOP. Great.

How will you know your engine is running ROP?

Not sure where you're going with this question. I would suggest you start full rich, and if leaning increases EGT you are ROP.

Personally, I would just operate according to the Lycoming recommendations, but I'm not making any recommendations about what you do.

I was discussing this topic with a guy who designs ECUs for a living. His comments were that
1) Peak EGT is very lean already and
2) EGT is a terrible way to set mixture. You have no idea what the actual lambda (mixture) is at e.g. 50F ROP/LOP. However, it is the best we have in aircraft due to the lead in the fuel.

I would be interested in a chart of lambda vs EGT - particularly if it showed whether it varied with rpm and manifold pressure but I can't find one.

yr right

18th Nov 2014, 01:59

Creampuff

18th Nov 2014, 02:12

Not sure where you're going with this question. I would suggest you start full rich, and if leaning increases EGT you are ROP.

Personally, I would just operate according to the Lycoming recommendations, but I'm not making any recommendations about what you do.That’s what’s so hilarious. You’ll be confident of where you think the engine is running, but blissfully ignorant of where the engine is actually running.

More comedy gold: 1) Peak EGT is very lean already and
2) EGT is a terrible way to set mixture. You have no idea what the actual lambda (mixture) is at e.g. 50F ROP/LOP. However, it is the best we have in aircraft due to the lead in the fuel.Seriously: that’s the funniest thing I’ve read in weeks. :D:D:D

Creampuff

18th Nov 2014, 02:35

I know exactly what you mean, yr right.

When I find the tools under my carpet out of a 100 hourly, the tooth fairy put them there. When the temperature probe is left disconnected out of a 100 hourly, the Unicorn did it. When the magneto advance is 2 degrees too far advanced out of a 100 hourly, the cat did it.

Engineers never make mistakes. Manufacturers never make mistakes.

The problem is never the appalling quality control or competence of manufacturers or LAMEs. Those cookd clys are always the pilot’s fault.

It must be the pilot’s fault, because the manufacturers and the LAMEs say so.

I’m begging you to save other pilots from the lies that I’m telling.

You know how to prevent cookd clys.

Explain the throttle, mixture and propeller settings that pilots should use, and what indications pilots should expect, to operate a piston engine the safe, yr right way.

Please.

andrewr

18th Nov 2014, 03:10

That’s what’s so hilarious. You’ll be confident of where you think the engine is running, but blissfully ignorant of where the engine is actually running.

More comedy gold: Quote:
1) Peak EGT is very lean already and
2) EGT is a terrible way to set mixture. You have no idea what the actual lambda (mixture) is at e.g. 50F ROP/LOP. However, it is the best we have in aircraft due to the lead in the fuel.
Seriously: that’s the funniest thing I’ve read in weeks.

I'm happy to entertain you. Perhaps you can tell me what lambda corresponds to 50F ROP and 50 LOP?

How does lambda at peak EGT compare to the lambda for maximum power? Maximum efficiency?

Creampuff

18th Nov 2014, 03:28

I have no idea nor interest in what the lambda is, because I know, from first hand measurements of the EGT and CHT of each cylinder, where each cylinder is on the lean curve, and I know what to do to put and keep each cylinder where I want it to be on the lean curve, to get the power and efficiency I need for various phases of flight.

But that’s not the point: Remember – I have no clue what I’m doing. Many years and hours behind an engine that I’m incompetently managing, and the lack of cookd clys has been mere luck. The cool CHTs have been a product of the cooling effect of the lead on the valves and the unicorn fart additives in the oil.

I’m just fascinated to know what it is you propose to actually do about your concerns, and how you will be able to work out whether your concerns have actually been addressed. Presumably as some stage you’ll be sitting in a cockpit in proximity to a reciprocating engine, with some knobs to play with and some dials to watch.

Andy_RR

18th Nov 2014, 03:41

Just remember Creamie, if the knob in your hand is red, you're probably doing it wrong

Jabawocky

18th Nov 2014, 03:45

Andrewr, what are you doing on the 27-29th of March 2015?

allthecoolnamesarego

18th Nov 2014, 03:55

How do we know when you run lop or rop. We don't we all dills us lames we have zero idea.
Panio tuner may be. But your not even a player Clinton. Your a sheep. Your just passing on information that you have be taught.

Funny thing is you can't lie to an engineer. You may try we may think you have told us a furthy but in the end we know what happens the aircraft tells us what happens they talk to us. We don't always need fancy gauges to tell us what's happen. You may think we are all fools but at the end of the day your only cheating and lying to your self.

You're is a contraction, that is, it shortens two words. In this case the word 'you' and the word 'are', hence: you're. An example could be; 'You are a fool'. We can use the contraction to shorten that statement (contract = reduce/shorten) to 'You're a fool". Easy!

'Your' is a pronoun, (possessive in this case).

How do we know when you run LOP or ROP? We don't. We are all dills us LAMES, we have zero idea.

Panio tuner may be. But you're not even a player Clinton. You're a sheep. You're just passing on information that you have be taught.

Funny thing is, you can't lie to an engineer. You may try, we may think you have told us a furphy, but in the end we know what happened. The aircraft tells us what happened, they 'talk' to us.

We don't always need fancy gauges to tell us what's happened. You may think we are all fools, but at the end of the day, you're only cheating and lying to yourself.

That might be a bit easier to read now.

:ok:

Jabawocky

18th Nov 2014, 04:02

Mach E, this is not really thread drift, it is part of the core of the issues.

I should not have flicked back a page, but talk about funny.

I asked this,
if you have an engine at peak EGT and you make it richer, which by your example means it will get cooler, why then does it get hotter (CHT) when the EGT is falling? And once past about 50 or so dF CHT will drop again.

And shortly there after our resident expert on all things from wind farms to law and valve failures responds with,

Why dose cht rise. Because the energy is being released into the Cylinder chamber and not out the exhaust. Hence that's why you don't get burnt exhaust valves when running rop. But then again what would I know !!!

Let me repeat this again, if at Peak EGT (where many have in the past recommended you run, and then richen it up a bit like yr right wants you to do, why does the CHT go up while the EGT gets lower?

I will offer a tip here, despite what yr right thinks, everything is actually 100% opposite to what he posted above. Including the valves burning from LOP ops. The reason the do that is either poor fit or poor valve guides. Running at high CHT's accelerates the problem. LOP ops can't do it any more than the other in fact the logic of it all would suggest less so due less pressure and temperature.

So please explain where Pratt & Whitney, Curtis Wright, (TCM and Lycoming also) and a whole bunch of others got it wrong.

:ok:

andrewr

18th Nov 2014, 04:11

I’m just fascinated to know what it is you propose to actually do about your concerns, and how you will be able to work out whether your concerns have actually been addressed. Presumably as some stage you’ll be sitting in a cockpit in proximity to a reciprocating engine, with some knobs to play with and some dials to watch.

Good question. Where would you get operating procedures for one of these engines, if you didn't know it all already? Ideally, it would be from someone who had been intimately involved in the designing and building of the engines. Someone involved in matching and testing engines for particular airframes, and who receives feedback and statistics about any problems and failures. Where would you find that sort of information?

No, I am not a subscriber to the John Deakin view that Lycoming know nothing about operation of their engine.

However

how you will be able to work out whether your concerns have actually been addressed

This is an excellent question for CASA on the original topic i.e. Jabiru. The stats quoted are a failure rate of about 1 in 1500 hours. This could be a problem in evaluating any fix. If there isn't an obvious cause of the problem, at that failure rate it might take 20-30 engines and tens of thousands of hours to concude whether a fix is effective. (Need a statistician to work out the real numbers.)

That assumes that the stats don't show an obvious cause where you could go back to the old configuration e.g. hydraulic lifters, as some have suggested.

Creampuff

18th Nov 2014, 04:47

Where would you get operating procedures for one of these engines, if you didn't know it all already? Ideally, it would be from someone who had been intimately involved in the designing and building of the engines. Someone involved in matching and testing engines for particular airframes, and who receives feedback and statistics about any problems and failures. Where would you find that sort of information?I see your point.

The millions of operating hours of data collected about the effect of mixture on EGT and CHT only apply to these piston engines:
- Briggs and Stratton
- Honda
- Jacobs
- Ford
- Chrysler
- Franklin
- Pratt and Whitney
- Wright Aircraft
- General Motors
- Harley-Davidson
- Lycoming
- Continental.

The laws of physics don’t apply to Jabiru engines. Best to get yr right to sort out the problem. :ok:

andrewr

18th Nov 2014, 05:04

For Jabiru engines typically the only control the pilot has is the throttle.

It is also possible to have an endless debate about Jabiru throttle settings - not too low etc. And for Rotax 912(S) there is the "avoid cruising below 5000 rpm" camp...

Creampuff

18th Nov 2014, 05:18

rutan around

18th Nov 2014, 05:20

Andrewr
How does lambda at peak EGT compare to the lambda for maximum power? Maximum efficiency? I don't know why you're pissing around with the fuel air equivalence ratio. You're dealing with the fuel pumped into your aircraft so fuel air ratio is good enough. ie the mixture

1 Maximum efficiency occurs when all the fuel is burned and some excess oxygen is in the exhaust gas. ie a lop mixture. 50* - 80* is good to ensure absolutely all the fuel is burnt.

2 Peak EGT all the fuel and all the oxygen is used up ( theoretically )

3 Maximum power occurs about 40* rich of peak.To ensure all the oxygen is burnt a small excess of fuel is used (slightly rich mixture ) The unburnt fuel goes down the exhaust. Efficiency is fairly good but not as good as at peak and less again than lop. 40* rop is very hard on the engine.

40* rop gives the fastest mixture burn (due to a shorter ignition latency period after the spark event ) This means all the mixture is burnt sooner than than is good for the engine. Sometimes the burn is complete at or just after top dead centre and sometimes even worse before TDC. This means maximum pressure occurs when the swept volume of the cylinder is smallest and the mechanical advantage (ability to impart rotational energy) is zero or actually negative.

This is very hard on the mechanical parts of the engine and it creates a lot of heat which you read on the CHT gauge. Imagine riding a bicycle and applying maximum pressure to the pedal at the top or just before the start of the down stroke. You may push as much as you like but nothing much happens till you obtain quite a few degrees of mechanical advantage.

The ignition timing on an engine is set so that maximum pressure in the cylinder occurs 5* to 15* after top dead centre. As it is a fixed ignition system a compromise has to be made and so it is set for normal mixtures.ie 40* LOP or more or 100* + ROP

andrewr

18th Nov 2014, 05:41

If I wanted to figure out what’s breaking a particular kind of piston aero engine (other than purely random failures), I’d set one up so that I could be sure that all cylinders are operating between about 40 and 50 degrees rich of peak on the lean curve, at high power and a relatively low cruise RPM.

That way I’d be giving the engine the toughest pounding that I could possibly give it. (Ssshhhhhh: Don’t tell yr right, but that’s ROP….)

I’d then apply time and observation.

I suspect most engine manufacturers are on top of that, and already perform similar tests.

It is probably something more obscure. Maybe something maintenance related, maybe something assembly related, maybe thermal cycle related. Someone hypothesized that it could be due to the mass of the hydraulic lifters because they are from a much larger engine.

The first thing we need to know is what are the common failures? Through bolts seems to be the main one being discussed.

Arnold E

18th Nov 2014, 05:43

Ultralights

18th Nov 2014, 05:43

And for Rotax 912(S) there is the "avoid cruising below 5000 rpm" camp...
Theres good reason for that!

it avoids this..
This is very hard on the mechanical parts of the engine and it creates a lot of heat which you read on the CHT gauge. Imagine riding a bicycle and applying maximum pressure to the pedal at the top or just before the start of the down stroke. You may push as much as you like but nothing much happens till you obtain quite a few degrees of mechanical advantage.

very similar effect on internal pressures as running LOP..... sharp drop of in pressures...and hence, temps..

the events described above, the high pressures, running at the worst ROP mixtures, i think are part, if not most of the issues facing the Jabiru engine failures... how do you snap a bolt under tension? with a lot of pressure.. repeatedly..

Jabawocky

18th Nov 2014, 05:44

rutan

You are getting your numbers mixed up, the max power is around 75-80dF ROP, and the highest ICP is around 40dF (30-50).

Cheers mate :ok:

Andy_RR

18th Nov 2014, 05:55

Wow, there's a lot of pilots here with opinions about engines with little data to back up said opinions.

Sadly, it appears that even CASA don't have much data, or at least they're not sharing the data to support their proposed opinion.

Maybe that's the way engineering works in these days of the service economy?

Creampuff

18th Nov 2014, 05:57

Andrew: All of those suggested causes relate to design, manufacture and maintenance. Surely it can only be the way the pilots are operating them that is causing the damage? (Just kidding. I added that just to goad yr right.)

Assuming that the cause/s is/are one or more of design, manufacture (including assembly) and maintenance, I’d still run the engine at the settings at which it’s getting the hardest pounding I could give it (40 to 50 ROP, lower RPM). That would also mean the thermal cycle would have the highest peaks. I suspect most engine manufacturers are on top of that, and already perform similar tests.You may well be right, but I wouldn’t be surprised if you aren’t. Testing at those settings assumes that manufacturers know that they impose the greatest stresses on the engine. If they knew that, it’s hard to explain why some POHs (albeit old ones) would still recommend operations at those settings. Sure, it’s the setting that will make the aircraft cruise very fast, but it’s not fun for the engine. :confused:

Creampuff

18th Nov 2014, 06:23

I find it interesting that this debate even occurs. I worked for many years in the 'experimental engineering' division of a major motor vehicle manufacturer. Now it appears to me that Lyco and Conti would have similar divisions. It also appears to me that some of you are saying that we did not have any idea what we were doing, (despite being employed in this are for many years) and a lot of you know more than the people that actually design and build the equipment. Jabba, I wonder how many people know more about your business than you do. On your standard, a fair few I would guess. (first time I have commented on this debate).It’s not about what people know.

It’s about what the data prove.

The data prove what settings result in the imposition of the greatest stresses on the engine. The data prove that 40 to 50 F ROP mixture is that setting, exacerbated by reducing RPM with an engine with fixed timing.

It may well be that you and all these divisions in Lyco and Conti know this. But the problem is: They don’t say this.

It wouldn’t be so bad if they said: “You’re giving your engine the hardest pounding you can give it, at 40 to 50 F ROP and low cruise RPM, but guess what: Our engines are built to take it and we give you a money back guarantee that you’ll make it to TBO!”

It would be even better if they went on to say: “Guess what else? You’ll give your engine less of a pounding if you operate much further ROP, or LOP, and our engine can take even more of that!”

But instead, the persistent folklore results in many engines being operated in the range where they are getting the hardest pounding they can be given.

And when something breaks it is, of course, the pilot’s fault!

And even more appallingly, if you produce engine monitor data to show first hand measurements of the temps running an engine ROP and LOP, and to show that the engine has been run for hundreds of hours at cooler CHTs than they would have been if the engine had been operated ROP, the cylinder failure is still the pilot’s fault! That cylinder failed because you were running the engine LOP! It wouldn’t have failed if you’d run it (hotter) ROP! It couldn’t possibly a manufacturing or maintenance problem! :ugh:

This is one of the reasons CMI’s going broke.

andrewr

18th Nov 2014, 06:32

Testing at those settings assumes that manufacturers know that they impose the greatest stresses on the engine. If they knew that, it’s hard to explain why some POHs (albeit old ones) would still recommend operations at those settings. Sure, it’s the setting that will make the aircraft cruise very fast, but it’s not fun for the engine.

Possibly because they are designed and engineered and tested to be able to run at those settings for the TBO of the engine?

There are also some assumptions about what is hard on the engine - specifically heat and high cylinder pressures. But if they were planned for in the design, are they really hard on the engine? If you are within limitations, not necessarily. Operating in ways that were not anticipated when the engine was designed may be harder.

Other things that could be hard on the engine:
- Long periods at low rpm. You may have less than optimum oil circulation etc.
- Low temperatures. Lead scavenging requires high temperatures to work properly. Lead deposit problems have been described in low compression engines operating on higher lead fuels than they were designed for, and Rotax etc. with liquid cooled heads.
- Low manifold pressures reportedly may cause problems with ring seating.

My personal opinion is that you are least likely to have problems if you operate in the way the designer expected.

Aussie Bob

18th Nov 2014, 06:57

Arnold E

18th Nov 2014, 07:02

you are least likely to have problems if you operate in the way the designer expected.

Since he is the one that knows the design intent.

Andy_RR

18th Nov 2014, 07:21

I am going out on a limb here but is it possible that some Jabby failures are due to a machined crankcase? I am sure there are other engines using this method but I have never seen one. Even my lawnmower has a cast case.

Most crankcases are machined at some point in their manufacture. There's no real data to support this hypothesis, is there AB?

Since he is the one that knows the design intent.

The design intent and the design results are often worlds apart. There's normally a development process in between which is used to minimize the characteristic flaws in a design. All engines have their weak points, some more so than others. Many of these points are attempted to be fixed by ADs and recalls, if not by "maintenance" alone. Others become "character"

Creampuff

18th Nov 2014, 08:05

Possibly because they are designed and engineered and tested to be able to run at those settings for the TBO of the engine?Yet so many of them don't make it to TBO.

Again, the data shows what one problem is, because there is a real life experiment going on in aviation land. A fairly homogenous group of pilots - fed about the same diet of folklore and facts during training - some flying brand X engines and some flying brand Y engines, and brand Y is suffering far more premature cylinder failures/valve problems. But what's the explanation? It couldn't possibly be the manufacture or maintenance of the cylinders and valves on brand Y engines. Gotta be a pilot problem! Get aircraft owners to pay for a fleet wide change! Further, a bunch of pilots flying brand Y LOP gets fewer pre-TBO failures that pilots flying brand Y ROP. LOP must be bad!

It all makes perfect sense.There are also some assumptions about what is hard on the engine - specifically heat and high cylinder pressures."Assumptions" is an odd way to describe the realities of the metalurgy involved in what is, after all, nearly century old technology. Why did the designers put a red line on CHT?

I'm confident that there is data to show how strong the materials comprising cylinders are at various heats, and what happens when various pressures are applied to them.Other things that could be hard on the engine: Could be. Might not be. What do the data show?

Certainly the data show that running the engine longer and more often is better than running it 1 hour every couple of months. Not sure what that has to do with ROP v LOP though.[Y]ou are least likely to have problems if you operate in the way the designer expected ... [s]ince he is the one that knows the design intent.So are you saying that the designers of piston aero engines never expected them to be operated LOP?

If so, it's astonishing that those designers were blissfully ignorant of the tens of thousands of piston aero engines that have been operated LOP for millions of hours over many decades as standard operating procedure.

Oracle1

18th Nov 2014, 10:34

Having fixed a few and flown a few here is my two bobs worth.

Jabiru engine failure modes,

1. Through bolts.

In the older solid lifter engines the tolerances would change often (for reasons I will expand on further in the next point) and unless you got the engines temperatures stable the user would have to constantly adjust the valve clearances so Jabiru decided to dumb the engine down by fitting hydraulic lifters. The mass of the solid lifter is tiny in comparison. Ergo large mass smashing back and forth pounding the thru bolts and they break.

2. Various Top End Failures.

The material chosen to manufacture the heads is ductile so that it can be CNC machined. The material has a higher plasticity when heated in comparison to the likes of a vacuum cast head such as Rotax uses. Jabiru finally recognized this when they started experimenting with vacuum cast top ends some three years ago but looked to me have made the same mistake as the coarse finned heads and didn't have enough surface area to transfer heat. Valves moving around in the guides and the seat as well as ladies waisting the valves from exhaust gases (stretching the valve in the exhaust flow, probably from insufficient diameter and surface area to transfer heat to an already hot guide) are all a result of heat retention and the ductility of the parent material.

3. Cooling problems Various

I have mates of mine who have persevered with Jabiru engines and now have many thousands of hours of reliable service from them. Anyone who knows will tell you to keep the CHT's below 110 C and the heads are a heap more stable. Then the solid lifter engine stops drifting in the valve clearance and presto no more tinkering there. Suddenly the through bolt tensions stop changing as well. These temps are easily achieved by opening the nostrils and putting extensions on the bottom of the cowls, careful checks for air leaks etc, no zoom climbs, all standard air cooling stuff.

4. Fuel Distribution

I am not going to expand on this because it is common to all aircraft engines and is the same old story, fit the engine analyzer now. In Jabiru's case they should just inject the engine, either electronically or manually.

In summary people should get of Jabiru's case. They have made some remarkable achievements on a shoestring budget using ingenuity and hard work. The air frames are a great product! Aircraft engine development is the holy grail and the big boys engines still f**k up all the time and at a much higher cost. However Rod Stiff needs to abandon the shoestring budget mentality (however altruistic) and start looking at more sophisticated production techniques and more custom parts rather than robbing cheap parts in mass production and working around them.

PS Don't bother arguing with Jaba on engines you will loose

Aussie Bob

18th Nov 2014, 10:36

Most crankcases are machined at some point in their manufacture. There's no real data to support this hypothesis, is there AB?

No data whatsoever Andy, as I said, I am going out on a limb, but who else anywhere uses machined from billet crankcases? Surley it is easier and cheaper, so why isn't everyone doing it? Just asking, I don't know myself.

dubbleyew eight

18th Nov 2014, 11:52

jabiru aren't unique in experiencing engine problems.

crankcase through bolts used to fail on VW conversions.
the cause was too heavy a prop bringing the harmonic vibration speeds down into the operating rpm range.

overheating heads were experienced by one of the european motorcycle manufacturers.
the solution was to move the transition to the exhaust pipe closer in to the valve seat. this took heat from the head and pushed it into the pipe which could be cooled more easily and wasn't as temperature critical.

the core challenge in fixing problems is to identify the actual cause.
sometimes it needs the calling in of some smart boffinry. (that's a hint jabiru.)

rutan around

18th Nov 2014, 12:02

so Jabiru decided to dumb the engine down by fitting hydraulic lifters. The mass of the solid lifter is tiny in comparison. Ergo large mass smashing back and fortI don't believe reducing unnecessary maintence and the potential for inducing oil leaks every 25 hours is 'dumbing down'. I for one encouraged Rod to fit hydraulic lifters every time I saw him. Even my old 55 Vauxhall had hydraulic lifters. People who like adjusting tappets need to get a life.

I don't think mass had much to do with hydraulic valve problems. I think it was more a cam shape problem. It allowed the valves to shut too quickly or open too slowly or something like that. Forgive me but it was a while ago that I heard the explanation.:uhoh:

I fully agree about the need to control cooling and the need for accurate gauges.

Radix

18th Nov 2014, 12:47

............

gerry111

18th Nov 2014, 13:23

Thank goodness that I've never flown with Creampuff!

(Along with his often demonstrated limited knowledge of how his IO520 actually works.)

There should be a law against people like him! :ok:

Sunfish

18th Nov 2014, 14:37

LOP/ROP arguments about Jabirus are missing the point; with a Bing Carburettor and no EGT probes, who would have the faintest idea of what is going on.

Furthermore, Jabirus issues have nothing to do with mixture and everything to do with basic mechanical design.

1. The lack of a head gasket makes the head/cylinder joint a weakness because of differential expansion and permanent distortion.

2. (1) means that valve clearance setting is problematic. That leaves valves vulnerable to sticking/burning.

3. Through-bolts are marginally too weak and clamping forces are not enough to prevent fretting without permanently deforming the heads (see 1.).

4. Perhaps most importantly, Jabirus use of fully CNC machined heads puts a limit on the number of cooling fins. the tool that cuts them has a maximum width/ depth ratio that cannot be exceeded ( its a machining thing) so there are not as many fins (more surface area) as ideally should be present to cool the head. A cast head with more and finer fins would be better from a cooling point of view.

Sadly, the last aerospace quality foundry that could have cast such heads was at CAC ands shut down due to stupid accounting practices that falsely indicated it was unprofitable.

5. Finally, the factory management either can't afford or won't contemplate product improvement, leaving them with no choice but to close business and sell it to someone who has the funds and attitude necessary for product improvement and professional customer service.

Jeez I'm glad I forgot about this motor.

Squawk7700

18th Nov 2014, 18:55

Sunfish I call you bluff on items 1 thru 4 B. You have been reading too many (other) uneducated posts on forums.

Eg,
You are saying that weak thru-bolts are causing fretting heads?

The jury is out on number 5.

Perhaps stick with whatever it is that you believe you do well in life versus Jabiru design engineering.

Creampuff

18th Nov 2014, 19:39

LOP/ROP arguments about Jabirus are missing the point; with a Bing Carburettor and no EGT probes, who would have the faintest idea of what is going on.Bingo.I am not going to expand on this because it is common to all aircraft engines and is the same old story, fit the engine analyzer now. In Jabiru's case they should just inject the engine, either electronically or manually.Bingo.

That way you can easily do this:Anyone who knows [Jabiru engines] will tell you to keep the CHT's below 110 C and the heads are a heap more stable.Listen to Oracle1.

Once you can control and measure EGT, you can set a mixture (and RPM) that doesn't result in the cylinders getting the hardest beating you can give them. Once you can control and measure a couple of key variables, you have a better chance of working out what's breaking, and why.Considering your 'confident' attitude I assume you have the data for that. Care to share so we can critique?No. I just made that up. :ok:

rutan around

18th Nov 2014, 20:59

Considering your 'confident' attitude I assume you have the data for that. Care to share so we can critique?Nah he's got nothing.

Oh except millions of documented operational hours on turbo compound radials and other big bore radials as used before the jet age.

The turbo compound engines fitted to B29s and Super Constellations went from 200 hrs- 600 hrs time between overhauls when run rich of peak EGT to 3,600 hrs time between overhauls when run lean of peak.

But hey what's a few million hours of documented evidence compared to pet theories , established old wives tales and information supplied by your lame / instructor God. It's the vibes.

Of course we should also ignore data generated at GAMI which uses the most advanced aircraft piston engine diagnostic machine in the world.

Oracle1

18th Nov 2014, 21:44

I don't believe reducing unnecessary maintence and the potential for inducing oil leaks every 25 hours is 'dumbing down'. I for one encouraged Rod to fit hydraulic lifters every time I saw him. Even my old 55 Vauxhall had hydraulic lifters. People who like adjusting tappets need to get a life.

Read my post again, once temperatures are stable there is no need to adjust the valve clearance. I cant be bothered adjusting valves either. Through bolt tensions also stabilize. In the case of Jabiru engines I will take the solid lifter every time.

Andy_RR

18th Nov 2014, 22:05

I'd like to point out, having done a bit of study on the subject in a past project, that fin surface area isn't the be-all and end-all of air cooling. Unfortunately, the problem is more complex than that because fin depth and width determines how much air passes through which is also a huge factor in heat transfer.

Bottom line is increasing the number of fins and decreasing fin spacing isn't necessarily a way to improve heat rejection and can reduce it instead.

Surprisingly, the best method to improve cooling appears to be to cowl each cylinder to precisely control the airflow through the fins, since air that passes over the cylinders rather than through the fins isn't doing much cooling at all. You have to do this in conjunction with eliminating cooling leakage though otherwise the general problem remains.

Oh, and crankcase problems? I heard from more than one person that the 912/914 series had crankcase fretting problem at some point during their history too.

Squawk7700

18th Nov 2014, 23:14

In the interests of disclosure, I run a 3300 Camit engine. They appear to have addressed all of the major Jabiru weaknesses and I’m very happy with the product. It has a starfish collar securing the flywheel, 6061 alloy heads, thicker through bolts than standard Jabiru bolts, piston squirters (aka Lycoming), angled rocker cams, oil filter locking mechanism, updated valves, alternator and more, so it’s clear they are working on the “fixes” and have what appears to be a great product.

I replaced the standard 3300 Jabiru engine in my aircraft with the CAMIT and continued with the standard factory cooling ducts and cowl etc and it simply ran too hot. The LAME had been treating the symptoms by replacing heat affected parts such as heads , valves and cylinders but not the cause of the over-heating. I won’t blame the LAME for a minute as these decisions are usually owner based, but in this case I have no evidence of either.

Basically, the installation was not suitable for either of these engines. I then embarked on a process of monitoring my engine (6 x EGT and 6 x CHT) and eliminating the issues that were causing the heat.

Airflow, airflow and airflow were the fixes, plus a small mixture alteration to bring the temps within tolerance.

Constrained by using a bing carby, I tried a multitude of mixture settings using a series of needle and main jets, some of which were ridiculously over-sized. Nothing worked in getting the CHT’s down until I increased the airflow.

I now enjoy running average CHT temps of around 125 degrees (~257f) with my max takeoff temps having never exceeded 150c (300f). Max OAT thus far 36 deg.

If anyone is interested in some pictures of the modifications required to achieve these figures, please contact me. As for those suggesting that you can’t perform these modifications due to certification constraints, needs to simply discuss with the factory.

Sunfish

18th Nov 2014, 23:23

Sqwawk, when the heads get too hot, they deform at the joint with the cylinder. That much is known. The joint leaks after deformation which is why Jabiru goes to positively insane lengths to instruct owners regarding cylinder head tightening. This should be a non issue if a modern head gasket was employed, even without going to the modern practice of designing the joint to employ plastic deformation of the head bolts during the tightening process.

As for through bolt failures, the "Cosi Fan Tutti" argument (every one does it) begs the question.

Creampuff

18th Nov 2014, 23:24

This is very important and interesting stuff, S7700.

With your series of needle and main jets, what were the corresponding EGTs?

Were you able to determine where each set put you on the lean curve?

Squawk7700

18th Nov 2014, 23:44

Too advanced for me there creamie.

I was simply adjusting mixture to achieve ideal egt figures based on >75% power and <75% power. Needle crafting was included to modify temps through the rpm range. It's not scientific and goes nowhere near LOP type discussions.

I proved (as the manufacturer said at the time) that adding fuel would be an expensive way to cool the engine and wouldn't work anyway. To richen the mixture from 20 to 28 lph has nil impact on CHT.

If we were talking figures closer to 18-19 lph then we would be talking more about LOP etc. I started well above this I suspect.

As for corresponding EGT's... The EGT's started high and gradually reduced as needle and main increased. Once you get too rich it's clear you are wasting fuel.

A $1000-$1500 investment in engine monitoring electronics is highly recommended.

Last check was 22lph. Without a TBI, LOP operations are just a dream.

Sunfish. Keeping head temps low is the solution, not fitting a gasket which will simply mask the problem.

Creampuff

18th Nov 2014, 23:57

Great stuff. :ok:

As a matter of interest, what was the impediment to trying sets that made the mixture leaner and leaner (noting that any EGT leaner than about 40 degrees rich of peak will start reducing CHT).

Squawk7700

19th Nov 2014, 00:12

Impediments were, time, effort, cost, skill and a Bing. Without a mixture control there would be little to no point I believe.

Creampuff

19th Nov 2014, 00:25

Bugga!

I just thought that if there were sets of needles and main jets that made the mixture increasingly rich, there might also be sets that went the other way…

Who knows: You might have ended up with ‘rough’ running, due to differences in the mixtures being delivered to each cylinder through a messy induction system, but then again, you might not have.

Looks like we’ll just have to wait for Jabiru to do what Oracle1 is suggesting they should do (as well as ensure sufficient air flow for cooling in any event).

Wally Mk2

19th Nov 2014, 00:59

It's all about choice, one can chose to risk beyond reasonable doubt ones life behind a Jabba donk or one can simply increase his/her chances of staying alive by choosing more known safe options:-)

Wmk2

andrewr

19th Nov 2014, 01:09

If you want to lean your (Experimental) Jabiru you can:

HACman Mixture Control Order Page (http://www.greenskyadventures.com/bing/HACmanorder.htm)

I know nothing about the company, and I wouldn't fit it to my own aircraft. I reckon it would be a gamble whether leaning improved the current situation or made it worse. If I had to put money on it I would guess it would make it worse, but I don't mind being proved wrong.

If you try it, please report back...

Creampuff

19th Nov 2014, 03:01

But Andrew, how do you know where on the lean curve each of the cylinders on these engines is running now?

If leaning from X to Y on the lean curve could cause damage to an engine, what if the engine is already running at Y?

Jetjr

19th Nov 2014, 03:04

Steady on with recommendations to lean out. There was a lean burn kit a while ago and caused many problems.
A key problem here is not the max or min EGT but the spread.
Those with full monitoring will often see 100 deg C difference in EGT between cylinders. It also changes in different modes of flight

All issues of rich or lean go out the window because you can have BOTH in the one engine at one time. I have seen some where they are fairly even.
Ive too done lots of playing with needles/jets etc and ended up as best I can get. Never over 710 degC, cruising under 690 BUT have sometimes one under 600 at the same time
With CHT, can get them near 120 most of the time, fitting under cylinder deflectors (the gull wings which used be installed on top) certainly stabilised temps and made them easier to manage.
Jabiru USA have a good PDF on air duct "tuning". Fiddly and time consuming but worth it.
Theres some evidence that this variation in fuel distribution is done upstream of carb. work continuing. Not much there so not easy to fix. It has been a thorn for years in carb auto engines too and they are water cooled! strong reason they adapted quickly to port EFI.

Many of the current throughbolt and valve issues are linked to hydraulic lifter introduction, sorry Rutan it wasnt a good move. Keep in mind you still have to open rocker covers anyway to tension headbolts.

rutan around

19th Nov 2014, 03:55

Many of the current throughbolt and valve issues are linked to hydraulic lifter introduction, sorry Rutan it wasnt a good move. Keep in mind you still have to open rocker covers anyway to tension headbolts. Maybe Rod should simply copy an IO550 and make his half size. Then the engines would see a TBO of 2 - 3 thousand hours and the owner would never have to adjust a tappet or remove a rocker cover.:E

andrewr

19th Nov 2014, 04:17

But Andrew, how do you know where on the lean curve each of the cylinders on these engines is running now?

I don't, which is one reason why I said it's a gamble. You were the one lamenting that there weren't needles and jets to go leaner (although I'm sure there are).

Also, you would be departing from the configurations which have at least had extensive testing and use to something which has probably had very little.

MAYBE it has been shown that you can't damage a Continental/Lycoming by being too lean. Even if true I don't believe that applies to all engines.

rutan around

19th Nov 2014, 06:37

MAYBE it has been shown that you can't damage a Continental/Lycoming by being too lean. Even if true I don't believe that applies to all engines. Oh dear :ugh:

yr right

19th Nov 2014, 07:35

rutan-around

Your theory that large capacity turbo compound engines increase there o/h from military to cilivan is in correct.

I have stated before this. The r985 for example had a 300 o/h life in the milTary. We had an o/h life of 1700 hours tbo with our engines. We never had one engine failure nor one cylinder failure nor one engine that never made tbo. We never ran lop.

Military have one thing over cilvil use. That is they have unlimited funds. This still is evident today.

To say they made extra hours because they ran lop is completely false and misleading.

We ran over 30000 hours with our engines.

Stop being a sheep. Go look up original P&W o/h times. Btw when they had a problem during the war the engine was removed and sent back to the USA they didn't fix very much at all.

LeadSled

19th Nov 2014, 07:50

turbo compound engines
A R-985 is certainly NOT a turbo compound engine.
All the big radials, including turbo compound engines, cruised lean of peak.
Tootle pip!

Sunfish

19th Nov 2014, 09:59

Meanwhile, while all you lot are reinventing the lean of peak argument, CASA has taken upon itself the role of judge, jury and executioner once again with no concrete evidence of anything at all except a feeling in its water that Jabiru engines are somehow so "unsafe" that their use, sale and production must be stopped immediately, for make no mistake, that is the likely outcome.

Furthermore, they are trying to set a precedent that would allow them to repeat this action anytime and anywhere they like with zero accountability. At least the SAAA has picked up on this precedent setting danger.

What CASA is doing is retreating from the standard of evidence based regulation in favour of voodoo economics.

To put that another way, you don't get to say "your engine is unsafe". Exactly which model and mod status is unsafe? What are the failure modes and why? Where is the statistical evidence that proves each of these hypothesis? What has the manufacturer proposed to remedy the proven defects? Is their proposal adequate or not? If not, why?

CASA's blanket ukase has to be stopped or it will be used again and again on engines and ultimately aircraft.

To put that yet another way, don't Vans aircraft have a rotten safety record? Aren't they extremely unforgiving in case of an engine failure? If Jabirus can be banned, why not Vans aircraft?

Having said all that, it appears Jabiru brought this on itself and I have no love for either it or CASA, but I'll be buggered if Rotax and all the others are going to get tarred with the same brush!!

Radix

19th Nov 2014, 10:39

............

rutan around

19th Nov 2014, 10:42

Your theory that large capacity turbo compound engines increase there o/h from military to cilivan is in correct. Where did I say one word about the Military? Engines don't know who operates them. Their life however depends on HOW they are operated.

halfmanhalfbiscuit

19th Nov 2014, 11:38

Sunfish makes a good point. The Jabiru thing is very general no model, serial numbers. Built between. Then you have the CVD case - CVD pilots are getting restrictions. No new evidence to support.

Hempy

19th Nov 2014, 13:32

Radix, it is a common misconception that CASA have an obligation to foster aviation in Australia. They don't, it's not mentioned anywhere in their Charter and certainly not practiced anywhere in the field.

CASA are the cops. They hate aeroplanes and pilots like cops hate crims. They'd be perfectly happy just to regulate UAV's.

rutan around

19th Nov 2014, 19:11

Radix said:-
. I'd be interested in a link to actual data rather than hear say. Get hold of the turbo compound operating manual written by Norman Rice based on material supplied by Wright Aeronautical Division.
It is called ' Basic theory of operation turbo compound engine'

If your local technical library can't source it you could always splash out and attend the next Advanced Pilots Seminar and get the book free. You might also learn a lot more about internal combustion engines. It's win win really because if you feel you didn't get your money's worth they will give you a full refund and you walk away with a free book.:E

Continental and Lycoming have been extremely successful in producing reliable engines so to say you understand more about their engines than they do is a bit arrogant. (Only a bit)I don't claim to know more about their engines than their engineers but I do claim to know a better way to operate their engines than that written in their operating manual by their marketing department. When the operating manuals are written by engineers the engines will last twice as long as they do now but that wouldn't make the sales department happy would it?

Creampuff

19th Nov 2014, 19:43

Again, this is what is so hilarious about these "arguments" (which aren't arguments at all).

So the all-knowing manufacturers produce a POH that says: "Lean the mixture and note the point that the temperature peaks and starts to fall. Increase the mixture until the EGT shows a drop of 25 degrees F below peak on the rich side of peak." (Quote from a real POH.)

I keep asking this question of the "experts" like yr right contributing to this thread, and keep getting no answer: How does the pilot know if all cylinders of an engine adjusted in that way are running rich of peak?

The fact that the pilot is blissfully ignorant of where the cylinders that aren't driving the EGT guage are on the lean curve doesn't stop them from being at peak, or lean or peak or richer than 25 rich of peak.

I suppose it raises the philosophical question: if a cylinder is running LOP in the forest, does anbody hear?

Maybe CHT depends on whether the pilot knows if the cylinder is running LOP: hotter CHT if she knows; cooler if she doesn't.

Data produced from the operation of tens of thousand engines operated for millions of hours shows the relationship between EGT and CHT. Those data show that CHT will be cooler at 25 LOP than at 25 ROP.

But nooooooo. Your clys will be cooked and your wings will drop off if you operate at 25 LOP instead of 25 ROP!

It's hilarious. :D

yr right

19th Nov 2014, 20:27

Quote
The turbo compound engines fitted to B29s and Super Constellations went from 200 hrs- 600 hrs time between overhauls when run rich of peak EGT to 3,600 hrs time between overhauls when run lean of peak.

Mmmm not sure how many B29s etc used in cilivan use ?

And not all big turbo compound engines used lop all the time ether. You can not compare apples to oranges or lyc cont to large cap P&W or wright engines. Example of the r985 was an example only of the difference between mil tbo and cilivan. Sorry you could not see that. Back now to tuning pianos

Mach E Avelli

19th Nov 2014, 20:37

C'mon people, stay focussed.
What can be done to appease CASA and perhaps save Jabiru?

My suggestions:

If the MTBF is 1500 hours, immediately impose a 750 hour TBO, or at least a top at 750 hours. Factory should offer this for cost of parts only and a nominal labour charge. If they were really pro active they would do it at a fixed price on a sliding scale according to the hours that the engine had already flown, ie cheap for 750 hours, more if the engine was nearer 2000 hours.
New production engines to fit gaskets, go back to solid lifters, better valves and a better fuelling system e.g. throttle body injection, multi point CHT and EGT probes as standard.
Jabiru to implement a reasonable core trade-in program, even if the old core is not much more than scrap.
Factory to offer a free operator training course with all purchases and after any factory overhaul. Extended warranty and TBO to those who attend.
If they can't warrant the product for at least three years or 750 hours and if they can't get the TBO up to that offered by Rotax maybe they need to shut their doors, as clearly the product is not 'fit for purpose'.
I fear the demise of Jabiru if they do any less.
Other suggestions?

Jabawocky

19th Nov 2014, 21:29

I think your all talking about the R3350 lads :ok: And just for Yr rights benefit they were run around 0.4lb/hp/hr and for a low compression ratio engine that is what? LOP or ROP? please tell me, just in case I forgot something ;)

MACH E,
The things you mention it gaskets, go back to solid lifters, better valves and a better fuelling system e.g. throttle body injection, multi point CHT and EGT probes as standard are all good improvement ideas. The valves I think are fine. It is more a matter of the valve guide material, and the head distorting affecting guide/seat geometry. Perhaps even rocker arm geometry. These are the things that break heads off valves usually.

Squawk7700

19th Nov 2014, 21:55

All good ideas.

Some ideas I like and some I've added.

Perhaps -

- Reduced TBO
- Core replacement at a fair price to get old engines out of circulation
- Reduced margin parts for these upgrades
- Release of affected serial numbers where possible
- Enforcement for owners (this is a major issue and one of the reasons for breakages - many of those that broke had not been upgraded)
- A cooling "kit." New baffles and ducts, something scientific and tested, that is a bolt on "fix." People like a "fix" or a "kit" to solve their problems
- Plenum chamber as an option for cooling like a real Lycoming style one

As for engine components

- Valves that don't warp
- Valve spring washers that don't break
- Thru bolts and nuts that fit
- Increased quality control through known-good suppliers (do they have a QA manager?)

I don't beleive head gaskets are a solution, they would just mask an existing issue.

Creampuff

19th Nov 2014, 22:05

What can be done to appease CASA and perhaps save Jabiru?1. Determine things called “facts”.

Is there a problem at all?

All machines break. Are Jabiru engines failing at a higher rate than other engines, or are there more Jabiru engines operating more hours, and the rate of failure has remained the same? It may be that the rate has remained the same, but there are more failures because there are more engines operating more hours.

Even if the rate of failure has increased, is that a problem? Have there been any serious injuries, fatalities or property damage? If not, what is the “problem”, other than the cognitive bias of punters?

2. Assuming there is a problem, determine a thing called the “cause”.

If some of the folklore-driven thinking evident in this thread is typical of the approach that will be taken by the manufacturer and CASA, Jabiru is, as a business, as good as dead. Let’s hope against hope that it isn’t the approach taken.

My suggestion would be to get people like Oracle1, jabba and his APS off-sider, on the job. They understand how engines actually work and how to actually operate them. Then you might have a better chance of nailing down the actual cause of the problem – if there is one – and options for actually dealing with it.

But aviation regulatory decisions in Australia are often unhindered by inconvenient considerations like facts and cause.

DonC

19th Nov 2014, 22:14

I haven't had any "breakages", but when you regularly have to do top ends at 300 - 400 hrs there's something wrong!

Squawk7700

19th Nov 2014, 22:59

We need to be careful to distinguish between "top end" overhauls and leaking valves.

Top end overhauls include new pistons, cylinder honing, conrod bearings and valves amongst numerous other components.

Jabiru valves cost $45 versus $285+ for a Rotax valve. Lapping in some valves on a Jabiru at a few hundred hours whilst not ideal is not of major financial disadvantage to an owner, but it's not a top end overhaul.

CASA comparing Jabiru failures to Rotax is floored given the reliability of the Rotax. It's a high bar to jump.

Arnold E

19th Nov 2014, 23:36

written in their operating manual by their marketing department.

Since we are all looking for facts here, what evidence do you have that operating manuals were written by marketing people. I know the service and operating manuals written in the car industry that I worked in, were written by either technicians or engineers and edited by engineers.:)

Creampuff

19th Nov 2014, 23:40

The APS people have spoken, first hand, to engineers in brand X and brand Y.

Engineers from those brands have attended the APS course.

If you think hard about what parameters potential purchasers of aircraft GA fixate on, when deciding what aircraft to buy, you'd understand why many old POH recommendations have the engine running around the point at which it's being beaten to death. Think hard...

Andy_RR

20th Nov 2014, 00:04

Well, this whole problem got an airing on national breakfast radio (http://www.abc.net.au/radionational/programs/breakfast/recreational-flyers-sceptical-of-jabiru-engine-ban/5905092) this morning, just in case some didn't hear.

http://mpegmedia.abc.net.au/rn/podcast/2014/11/bst_20141120_0836.mp3

yr right

20th Nov 2014, 00:20

Clinton you forgot to add this.

Written and spoken for and behalf of APS.
Please note that APS don't accept any resonpsoability for lose or damage to your aircraft , aircraft systems or aircraft engine after you have done the non approved APS training course.
APS accepts no resonpsoability for any actions which may cause death or injury to any non approved data or lack of data or any data which contravenes any manufactures data or the pilot operating hand book.

Think that covers it.

Cheers

Squawk7700

20th Nov 2014, 00:20

Nice work by President Monck. Very confident in his replies, well informed and gave a good perspective of the impact of all of this.

Creampuff

20th Nov 2014, 02:00

But yr right, it doesn’t matter whether or not APS accepts responsibility.

Anyone can sue them for any damage, death or injury caused by their horrendous lies. APS don’t require anyone to sign a release or indemnity and, in any event, it wouldn’t work to protect them from liability if they did.

Surely you would agree that because the APS course and data are “not approved”, lots of people relying on their dangerous, invalid information and recommendations provided during the course would be blowing up their engines and killing people, left, right and centre? In a litigious country like the USA, they’d have been sued to oblivion years ago.

Yet they continue to exist and thrive, litigation free. How could that be?

It couldn’t possibly be because the course is based on data gathered from the operation of tens of thousands of aero piston engines over millions of hours, as well as the data gathered from the most sophisticated aero piston engine test and measurement cell on the planet. It couldn’t possibly be because of the first-hand experience of people who (unlike you) pilot aircraft with engines operated in accordance with LOP procedures that were settled decades ago.

It must be because APS mesmerise people with their voodoo and folklore.

I do sometimes get a tinge of guilt at shooting a fish in barrel, but you do lead with your chin…

Tell us, yr right, at what mixture setting will a piston aero engine’s CHT be lower:
(a) 50 degrees F rich of peak.
(b) 50 degrees F lean of peak.

(PS: I have no direct or indirect financial interest in APS. My only interest is in dispelling the myths and folklore spread by dangerously ignorant people.)

Avgas172

20th Nov 2014, 02:32

Ooo ooo ooo, did this one in first year apprenticeship test
Answer : a
:E

Ex FSO GRIFFO

20th Nov 2014, 03:20

From You-Know-Who.....

Issued at 11.31 am today (WST)...

Civil Aviation Safety Authority - Consultation Draft ? CD1425SS (http://www.casa.gov.au/scripts/nc.dll?WCMS:STANDARD::pc=PC_102279)

Worth the read, particularly if you carry..(shudder)..passengers..!! (Proposed...)

No Cheers :sad:

Squawk7700

20th Nov 2014, 04:03

Fso is that the amendment that came out on Monday? Someone else said it came out today too which is strange.

Ex FSO GRIFFO

20th Nov 2014, 04:10

It says its a 'Consultation Draft'......

'Proposed' changes only at this stage I would think...

Cheers:ok:

Squawk7700

20th Nov 2014, 04:24

Oh so you just spotted that. It was released last week which spurred this discussion. The amendment was this Monday gone. Now I'm on the same page.

Ornis

20th Nov 2014, 04:26

It's very difficult to get adequate cooling of the heads and even when CHTs are within limits the tappets need adjustment every 25-30 hours. Hydraulic lifters hide the valve recession and head embedment.

It's very difficult to keep the EGTs within limits; if you run the engine lean a valve will break and you're looking for a field, not a graph.

yr right

20th Nov 2014, 04:31

So Jaba whoops I meant Clinton.

I'm sorry I'm not ignorant. Just because I'm not a sheep and have to follow the leader dose not make me one. All I've done is dispelled the lies that have been told. Case in point tbo life's.

Now as your such a expert on the way a piston engine works perhaps you can tell me what is a burnt valve and how dose it happen. Then what is flame front and what relationship dose it have with the mixture of an aircraft engine. Then perhaps tell us what part of an aircraft engine parameters is the most extreme. Then why is it un nessrary that APS dose not have an approval for the course that they teach when EVERY other course must have ?

Now onto the Jaba engine.

For casa to effectively ground this engine they must show a due cause. If this engine has suffered engine failure rates greater than is to be expected then what is the problem.

If the engine is so critical on mixture then there is an problem which needs to be addressed. Been a long time since I have looked after one but the early 6s that locked up the crank was not impressive at all.

Creampuff

20th Nov 2014, 04:55

[I]f you run the engine lean a valve will break and you're looking for a field, not a graph.What, precisely, do you mean by ‘lean’?

Every fuel/air mixture that supports combustion is ‘lean’. It’s just that some of those mixtures are on the rich side of peak EGT and some of them are on the lean side of peak EGT.

It’s too hard for yr right, but you can try the quick quiz too:

1. At what mixture setting will a piston aero engine’s CHT be lower:
(a) 50 degrees F rich of peak EGT.
(b) 50 degrees F lean of peak EGT.

2. At what mixture setting will a piston aero engine’s CHT be lower:
(a) 100 degrees F rich of peak EGT.
(b) 100 degrees F lean of peak EGT.

3. What EGT is hotter:
(a) 75 degrees F rich of peak EGT.
(b) 75 degrees F lean of peak EGT.

Creampuff

20th Nov 2014, 05:23

Then why is it un nessrary that APS dose not have an approval for the course that they teach when EVERY other course must have ?It’s because the APS people have mesmerised the regulators, too.

Or …

Maybe, like your understanding of engine management, your understanding of the aviation law is deficient.

(Surely the village of which this guy’s the idiot has a responsibility to save him from embarrassing himself so much.)

BTW: The correct answers to the quick quiz are:

1. (b)

2. (b)

3. Trick question: The temperature of the exhaust gas at 75 degrees F rich of peak EGT is the same as the exhaust gas at 75 degrees F lean of peak EGT.

Ultralights

20th Nov 2014, 05:34

genuinely interested in seeing the answers to the questions above....

dammit creamy, i was hoping to see some responses and the reasonings before you posted he answers

Creampuff

20th Nov 2014, 05:45

Don’t worry UL. Someone will almost certainly chime in about lead lubricating the valves soon, and the “argument” will continue… :ok:

yr right

20th Nov 2014, 08:10

So Clinton
You done one course and now your the instant Areo engine expert.

So here we go.

How may days this year have you spent in a maintence shop.

How many services have you done this year or ever

How many Ad eng 4 have your carried out.

How many engine changes have you done

How many cylinder changes have you done.

How many fcu changes and set ups
have you done.

How many mag changes have you done.

How many engines have you released

And once again you still have zero understanding of flame propergation and the damages that can occur

rutan around

20th Nov 2014, 08:24

yair Creamy some more questions

How long have you known the earth is flat.

How long have you known the sun orbits the earth.

Millions of people believed-believe? this so it must be right.:confused:

Aussie Bob

20th Nov 2014, 08:28

Millions of people believed-believe? this so it must be right.:confused:Let me fix that for you Rutan ...

Millions of people believed-believe? this so it must be yr right.:confused:

Squawk7700

20th Nov 2014, 08:38

Take it easy with the insults chaps, there's enough mis-guided nut-job forum-trolling failed political candidates on other forums, we don't need them coming here to get their jollies too :ok:

Creampuff

20th Nov 2014, 09:18

How may days this year have you spent in a maintence shop.

How many services have you done this year or ever

How many Ad eng 4 have your carried out.

How many engine changes have you done

How many cylinder changes have you done.

How many fcu changes and set ups have you done.

How many mag changes have you done.

How many engines have you releasedI love it when he's goaded into dropping the dyslexia schtick!

Solid gold. :D

gerry111

20th Nov 2014, 09:33

That was quite readable, for a change. Now we need to work on his punctuation. :ok:

rnuts

20th Nov 2014, 10:26

Keyboard warriors :mad: pathetic !!

Hempy

20th Nov 2014, 10:31

yr rihgt,

- how many return customers do you get? How many have a choice?

- is it easier to get away with releasing an engine when no one can understand what you've written on the MR?

- how many hours this year have you spent over-billing people?

- how many burnt clys on the hangar floor come out of aircraft you regularly maintain?

edit: rnuts you had to be there..

Ex FSO GRIFFO

20th Nov 2014, 11:17

Hi Mr SQ,
I opened this particular email for the first time today... At 11.31 or whatever it was. Congrats for you getting it last Monday.......

I thought it may be 'of interest' to Jabiru drivers.

Cheers:ok:

Squawk7700

20th Nov 2014, 18:27

All good exfso, though you were alerting us to yet another amendment. Glad it wasn't one.

yr right

20th Nov 2014, 19:25

So Clinton I would assume the following

How may days this year have you spent in a maintence shop.
One hour to drop aircraft off one to pick it up.

How many services have you done this year or ever
Zero
How many Ad eng 4 have your carried out.
Zero
How many engine changes have you done
Zero
How many cylinder changes have you done.
Zero
How many fcu changes and set ups have you done.
Zero
How many mag changes have you done.
Zero
How many engines have you released
Zero

So that make you an expert.

Humpy dumpty

We'll actually we would have near 100 percent return rate in fact we picking up a lot of work. And as for lame over charging we'll not sure lame do the billing Any way please feel free to bring your aircraft here and we look after to you. I'll make sure you get the special treatment you deserve.

yr right

20th Nov 2014, 19:36

And as for flat earth that's easy to fix.

Do what every other aviation course product aircraft has to do before it can be used.
Get it approved.

Wunwing

20th Nov 2014, 20:25

I've been watching this thread and many other on ROP/LOP for some time and I'm becoming more incredulous by every post on the subject.

My background is 20,000 hours + operations on jets,some time on big pistons and I have been a LAME (both airline and GA) although not engine endorsed.

What I find so concerning is for the most part I have worked under a rigid set of rules and procedures which self evidently worked well. Possibly this was because our beloved regulator had very little say in them or possibly because everyone knew what they were doing.Whatever there was a clear understanding, internationally and locally of how things worked and why.

What I'm seeing here is thread after thread of everything from hard facts to "witch doctor" stuff. We've had piston engines since Orville and Wibur etc and we still dont seem to agree on how they work?Its hard to recognise this as part of the same industry that I was familar with. Thinking about it its part of the reason that after a lifetime in an industry that I loved to be part of, I walked away from it totally.

Getting back to the thread, I hope that Jabaru get things sorted but if this thread is anything to judge where things are at ,I wouldn't hold out too much hope.

Wunwing

Jabawocky

20th Nov 2014, 21:13

Now onto the Jaba engine.

It is a Lycoming IO540…..thanks for asking, 1100 hours of which 10% (climbs) are Rich mixture ops to a target EGT, and the 90% remaining are LOP cruise and descent.

If you are referring to JABIRU engines, perhaps call them that, it might save the confusion.

I notice that you have once again not answered my question from two days and pages back, ignored Creamie and started on a tirade of garbage in response.

And seeing you are so smart please explain to me what an approved course is and how one would actually approve something to which there is no approval criteria to meet in the first place. :ugh:

And which parts of a POH are approved as part of the FAA certification? :E
How many engineering degree/associate degree/diploma/ or tertiary studies have you done?
How many FAA certification projects have you done or participated in?
How much detonation testing have you done or participated in?

Answer some of the questions in the past with your best efforts and when I get some time in the next few days I will answer some of your questions of the last day or two. In particular the cause of burned valves. This is one of the biggest Old Wives tales areas of all time.

Jabawocky

20th Nov 2014, 21:22

Wunwing,

The 20,000 hours of jet time you have participated in has been a tiny part of the problem. The invention of the jet engine and the jet age. All the knowledgable folk, engineering effort and focus was shifted from piston to jet. As a result 50 years ago the trouble started.

There is no Witch Dr stuff in the science of combustion, it has been well known and documented since pre WWII and the basis for much of the APS class that "yr right" seems to fear so much. In fact that knowledge base got lost with the advent of the jet.

The fact that the guys back 50 years ago had it right, and with modern data collection and development by a small few in the last 15 -20 years simply proves they had it right back then, speaks volumes.

The facts are the fuel burns the same today as it did in the 40's and before, the cylinders know no different either. What happened was lots of technically unsound stuff crept in and folklore was made. Most of which created a big drift between knowledge that was correct and that which was misguided. The cause of this was not understanding the difference between correlation and causation.

hope that helps.:ok:

Aussie Bob

20th Nov 2014, 23:36

MAYBE it has been shown that you can't damage a Continental/Lycoming by being too lean. Even if true I don't believe that applies to all engines.

Some few pages back Andrew wrote the above. In part he is correct, here is my experience of running an O360

First you need an engine monitor that provides data on all cylinders and measures fuel flow, you then observe the following:

Lean till she runs rough then enrichen slightly for smoothness as per the Lycoming book and you quickly realise that at this point some cylinders are lean of peak and some are rich of, or at peak EGT. Then discover that small changes in throttle setting and RPM will result in changing CHT's without touching the mixture at all. Adding more fuel via the mixture has very little effect on CHT. If you want "fuel" cooling you quickly discover that it is only achieved by very high (way above the manufacturer's data) fuel burn.

Play a bit more and you discover that there are settings where all cylinders are pretty well even and LOP operations are possible. On my engine it is number three cylinder that gets the hottest. It is far faster and easier to cool this cylinder by leaning the mixture more till this cylinder is LOP. If there is a lean "stumble" a bit of carby heat can be applied. For long distance cruising I find 26" MAP and 2450 - 2550 RPMs with a fuel flow of around 31 litres per hour gives me about 60% power with all cylinders under 350 F. You could not do this without the monitor.

Andrew states that this is not possible with all engines and he is correct, without the engine monitor it is not achievable and if the engine has a big gap between where the first cylinder peaks and the last cylinder peaks that will also make it impossible but these gaps can (most likely) be rectified.

If I owned a Jabiru (heaven forbid), the very first thing I would fit would be an engine monitor followed by water cooled heads. Next would be a throttle body injection unit so I could adjust the mixture inflight. Without engine monitoring and CHT correction where needed I think the Jabby failure rate will remain constant.

Without the proprietors attitude changing I can also see Jabiru failing. Our school had a through bolt failure at 300 hours. We were told it was "lack of maintenance". No warranty but a tiny bit of help on a new engine. Pure BS.

I still think the machined crankcase is also to blame. Where in the world is anyone else doing this? It is nothing but a cheap alternative to casting with the correct metal. If it was any good then everyone would be doing it.

Andy_RR

21st Nov 2014, 00:08

I still think the machined crankcase is also to blame. Where in the world is anyone else doing this? It is nothing but a cheap alternative to casting with the correct metal. If it was any good then everyone would be doing it.

The fully-machined billet aluminium block is a red herring, Bob. If the material is selected correctly and the design is good, it should be much more consistent than a casting which can be notoriously difficult to control quality on.

There are lots of people in the world (https://www.google.com.au/search?q=billet+aluminium+block&espv=2&biw=1920&bih=955&source=lnms&tbm=isch&sa=X&ei=WY5uVKXwLIXTmgXtz4KgCg&ved=0CAYQ_AUoAQ#facrc=_&imgdii=_&imgrc=RZHLlxyKcmXh6M%253A%3Bvmh27HZ-_3hAgM%3Bhttp%253A%252F%252Facimg.auctivacommerce.com%252Fim gdata%252F0%252F2%252F8%252F2%252F9%252F1%252Fwebimg%252F464 1689.jpg%3Bhttp%253A%252F%252Ff-bodyworld.com%252F500-Cubic-Inch-Billet-Aluminum-LSX-Block-P3104505.aspx%3B500%3B342) making billet blocks for high performance/race engines.

I think ULpower are another company using billet blocks for the LSA market. It's a great way to achieve low volume, high quality parts. Bear in mind that a large proportion of military airframes are machine from solid too.

Mach E Avelli

21st Nov 2014, 00:30

Aussie Bob's description of running LOP is nicely put. The flight engineers of olden days did much the same thing with the big radials. Only difference being they had 28 or multiples of 28 cylinders to fiddle with, so it was a full time task.
Unfortunately all this is totally academic for the standard Jabiru setup, where the pilot has no control over mixture in flight.
Other than expensive modifications (and until we have an outcome from CASA I for one won't be spending a cent on my aircraft) all that can be done in the short term is to keep a careful watch on compressions and pull the plugs every 25 hours. It is said that plug colour is meaningless if running on PULP but I reckon if three were uniformly black and one was a lighter shade of grey, it would indicate something irregular.
Other more knowledgeable folk invited to comment.

yr right

21st Nov 2014, 01:14

Creamie or Clinton which is one in the same. You already admitted that before. Or do you use creamie as your ultra ego. Maybe you may require some sort of medical help not from the cruch of Scientology but cause they don't believe in that sort if stuff.

Jabawocky

21st Nov 2014, 02:36

Steve, when are you going to answer some serious questions in some attempt to actually learn something, from someone who is actually willing to help.

Willing, but patience running out.

Jabawocky

21st Nov 2014, 03:00

This was emailed to me today. Worthy of a read.

To Whom it May Concern,
The basis of the meeting with CASA was in essence to say that our engine
incident rate was higher than Rotax based on flying hours and this was the sole
basis for punitive action.
CASA refused to recognise our overall safety in regard to fatalities and serious
injury where we have an outstanding record. We tabled statistics from the United
States which showed us to be the safest LSA aircraft in the United States. This
was disregarded. You may see these statistics at the following link.
http://flightdesign.com/files/Media/The%20Aviation%20Consumer%20-
%20LSA%20Accidents.pdf= Similar statistics don’t seem to be collected in
Australia or they are being withheld.
CASA stated that they had not researched the engine failure rates in any details to
ascertain if the failures were the result of operational, maintenance, or design
related factors. They did not release to Jabiru the actual statistics they had on
hand of engine failure rates. There is no international standard for the reliability of
piston aero engines and to compare one manufacturer with another is without
precedent. CASA also stated that there had been a spike in the incident rates on
Jabiru engines. This statement was refuted by the RAA who had on hand data
that showed there was no spike and this was tabled at the meeting. The fact that
CASA states that Rotax statistics are better than Jabiru statistics is not a point of
law and cannot be enforced under law.
Our own research indicates two failure modes, through bolt failures and valve train
failures which are the major contributors to the statistics. Our research and
statistics also reflected that the majority of these failures occurred in hard working
flying schools using 2200 engines. Engines used for private applications have
virtually no through bolt failures on our records. Our latest research and statistics
tell us that the introduction of roller cams has to date eliminated valve train failures
and the introduction of 7/16 through bolts in production engines has to date
eliminated through bolt failures. We have also introduced valve relief pistons which
do not allow a stuck valve to impact the piston. These pistons are now standard
and have been used on all overhauls and repairs since August 2013 and were
introduced to production in October 2013. We are also upgrading engines to the
current spec at owners request at major service intervals such as top end
overhaul. CASA were intently interested in our analysis and research which
justified the introduction of the latest modifications. To this end they have agreed
to come to Bundaberg and review our engineering development. We welcome this
move.
The problem is getting smaller by the day. It should be put in to perspective that
the incident rate quoted by the RAA has been 0.03% in some 90,000 movements
of Jabiru Aircraft which is a very low number and translates to 1 in 3,300 take offs.
Our own research and statistics establish that if we eliminate through bolt and
valve train failures the statistics may very well be more favourable than Rotax.
Our engineering efforts over the last three years have been to address
predominately these two failure modes that developed after years in the field.
Several Service Bulletins have been issued however we have no way of knowing
the take up rate of these Service Bulletins.
We are in the process of implementing contacting every flying school to ascertain
the configuration status of each Jabiru engine they operate. We will then suggest
individually a preventative program.

Aussie Bob

21st Nov 2014, 04:02

Thanks for the link and info Andy, my comments are from reading other info which could well be wrong but also from my own experience as an hobby machinist where external dimensions of billet alluminium can change when internal material is removed which of course can be fixed or allowed for. The milled from billet crankcase also looks really neat. A Jabby engine is a great display to show "interested in aviation" folk.

Another story I have heard is that the UL engine came about by someone producing a Jabby engine and asking for something better. The first thing they did was cast the crankcase. Perhaps just a story. This industry is full of them.

Squawk7700

21st Nov 2014, 04:10

Copying things doesn't always work eh!

Have been watching someone replace a head gasket on a Ssanyong, made under licence from Merc. Ouch !

Will be interesting to see how the UL pans out.

Section28- BE

21st Nov 2014, 04:18

Several Service Bulletins have been issued however we have no way of knowing the take up rate of these Service Bulletins.And hence, no way of accounting for the mod status of how many engines...........???

rgds
S28- BE

Arnold E

21st Nov 2014, 07:51

And hence, no way of accounting for the mod status of how many engines...........???

And who's responsibility is that??

MakeItHappenCaptain

21st Nov 2014, 11:04

All good to have specialist and expert operators modifying and getting full life out of these engines, but if Joe Average can't get the same results, there is a problem.:cool:

halfmanhalfbiscuit

21st Nov 2014, 17:59

Quote:
And hence, no way of accounting for the mod status of how many engines...........???
And who's responsibility is that??

TC holder of the airframe and engine have responsibility to support continuing airworthiness.

Jabawocky

21st Nov 2014, 18:33

TC holder of the airframe and engine have responsibility to support continuing airworthiness.

That would be nice, but in RAAus ? The manufacturer can do all they like.

yr right

21st Nov 2014, 19:40

Quote:
That would be nice, but in RAAus ? The manufacturer can do all they like.

Please
Explain.

The TC holder still has a duty of care. In this case it is a rare thing that the airframe and end engine is the same manufacture

Not having much to do with them only lightly over the years though if you find a proplem with a aircraft you report it. If a SB is done its reported in the log book not back to the manufacture. If it's an AD and it's found you report it back to Casa.
The Jaba engine in this case is no different to an other engine mod status Lyc or tcm don't know whyere their engines are ether.
All that info is in the log book.
Large turbine engines are the only exception to this.

What is more concerning is if what the email said is true ( not doubting it but) is casa attitude. Sounds like the usual vindictiveness from casa. To point the finger and not show why the finger is being pointed is just a degrace.

Sooner we get a royal comesion into casa the better. Hunt the vermin out charge them and goal them.

Jabawocky

21st Nov 2014, 23:23

I think it is best an RAAus expert should answer that. As you clearly do not understand the situation with RAAus, how it is different to GA, and you refuse to listen or learn from anything I post for your benefit.

Hopefully someone will explain what I said better than I could.

PS: how are you going with my simple question from a couple of pages back?

Hempy

22nd Nov 2014, 00:21

please feel free to bring your aircraft here and we look after to you.

That's the funniest thing you've written in 12 months. Steve, honestly, I wouldn't let you touch my lawn mower let alone anything else with moving parts. You've successfully advertised your real lack of technical knowledge quite adequately during your time on PPRuNe.

So umm thanks, but no thank you.

Section28- BE

22nd Nov 2014, 02:18

Thanks Jabawocky- for your comment/s, awarness or experience as it were....

At the get go, Nil experience with RAAus/or the Jabiru itself, and may or may not understand the situation as well as those involved- but have friends with family who operate one, with all manner of family and children onboard from time to time......... as one does. The machine, 'I believe' to be on its 3rd engine.

From an outsider or broarder Aviation / Saftey System standpoint, it would appear that, 'they've' identified 2x Modes of Engine Failure- being, 1) failure of the Valve Train and 2) failure of Engine Crankcase Through-Bolts. With both issues going back 'some' (considerable) period of time.

To address/mitigate these issues (that to me, 'appear' repetitive and indeed systemic), the manufacturer has issued a series of Service Bulletins, over time- that, as pointed out (above) are not in themselves 'prescriptive', for want of a term....- without going into defined definitions.

The issues 'appear' to me, to be beyond say the repetitive failure of an Accessory Drive for example- indeed both result in significant/total failure of the engine/power plant, and resultant Thrust.

If one ran these issues through a James Reason Safety Model (as the rest of Commercial/RPT Aviation has to do) at what point, given the longevity of the matters, do (/did) the holes start lining up in the cheese..........???, and is something prescriptive, auditable and/or accountable required at this time, be that an Airworthiness Directive or some such....????

Is that where The Regulator (/and RAAus) are now at....????

Rgds
S28- BE

Note: in no way endeavouring to be provocative- and wish all involved well in resolving these matters- affecting at the end of the day, an AUS Manufacturer.

Jetjr

22nd Nov 2014, 03:36

Almost all the engines are not certified
Same for airframes
LSA is toally under manufacturer control for modifications

Only -c versions carry any certification

thorn bird

22nd Nov 2014, 03:40

Section 28,

we have moved way beyond James Reason now, haven't you heard?.

The new model in Australia is the beyond all sensible reason model, (BASR) as espoused by the head of the ATSB.

Section28- BE

22nd Nov 2014, 04:12

thorn bird-

Yes, indeed............... I do apologize, and shall immediately take myself out and get me a proper good 'BASRing'......!!!!!

Again, many thanks for pointing out my state of aspirational delusion.

Rgds
S28- BE

Oracle1

22nd Nov 2014, 04:33

Ungermann and his cronies at CASA have not thought this through. Like a blinded wounded and angry beast CASA is looking to smash any remaining resistance. However unlike GA the target is a group of thousands of rich guys who own toys that they have bought specifically to get away from CASA's b*llsh*t. Most of them have no clue how their engine goes bang and just love Rodney's low cost model. This is no struggling small aviation business living from week to week on cash flow that CASA can strangle. This is thousands of rich guys who ain't going to like their machines being rendered useless and cop the value of the aircraft being reduced too nothing, on the basis of a gut feeling from CASA without any solid evidence. Owners will ask for all of this in the "discovery process". And after all was it not CASA who granted certification for the engine in the first place. For CASA to issue such an inflammatory proposal when they don't seem to have their ducks in a row, why not make the threat privately first?

CASA if your reading boys the Lilliputians are coming for you. Can wait to see the class action, its going to be f**king hilarious. Some parasite lawyers will be touting already :D

Wallsofchina

22nd Nov 2014, 05:32

The only sticking point in that argument Oracle is that the rich guys wrote to him about the engine failures and asked him to do something.
Now they aren't happy with what he's proposing to do and want to go into reverse.

Oracle1

22nd Nov 2014, 05:50

Who are these rich guys, I would like to know who wrote in and asked for their plane to be grounded and devalued. There are many other ways to skin the cat rather than coming out with such draconian measures. Once again CASA's judgement has shown to be sadly lacking when it comes to the amount of force required to obtain an outcome. This should have been handled privately.When push comes to shove the reaction is always entirely predictable if people are losing money.

Squawk7700

22nd Nov 2014, 07:03

Ignore him Oracle, he got kicked off here for being a tool and this is his second post back after a holiday.

The rich guys own GA aircraft like the imported Marchetti I saw today unloaded from the US, the imported US aircraft like the Cirrus aircraft and the likes of the euro imports from countries I can't even spell the names of.

This "grounding" affects budget conscious pilots, ma and pa pilots that have had doors opened up to them by the development and sale of the Jabiru. Pilots that would otherwise not have been able to afford to fly an aircraft prior.

Aussie companies with a lot of employees and many many more behind the scenes making components as sub-contractors. The fuselage, wings, brakes, wheels, engines, flaps, radios, professional builders... Jabiru themselves and their employees are really just a warehouse, project management and development company. It doesn't just affect Jabiru themselves!

This isn't looking good for anyone involved.

There are more Jabiris flying in South Africa than Cessnas! I'm sure they are well across all of this!

yr right

22nd Nov 2014, 08:15

Jaba
It may be a little surprise to you but not all Jabas are on on the RAA some are even under VH rego. Btw I hold a RAA lic.

yr right

22nd Nov 2014, 08:17

Humpyy dumpty I was having a go at you. I'm
Not interested in your little toy. DF.

yr right

22nd Nov 2014, 08:27

Squawk7700

22nd Nov 2014, 08:32

Yr_right, are you sure you have an RA Licence?

I'd say you have an RA-Aus issued pilot certificate.

thorn bird

22nd Nov 2014, 09:15

Aww come on guys, this is all part of the plan.

CAsA have just about bought the certified part of the industry to its knees with part 61. Part 135 will be the coup de grace.

The plastic fantastic brigade are easy. Bugger up their power plant and their screwed, easy peasy.

cockney steve

22nd Nov 2014, 10:33

No engine enelayis gauges just what the aircraft has feel smell and real knowledge.
No computers to tell you what a wrong.

That there's yr. problem. Back when I were a lad, Motor-cars had a toothed ring in the centre of the steering wheel. engaging with this ring were levers for Advance-Retard, Mixture, and throttle.
The driver juggled these whilst usinga non-syncromesh gearbox,mechanical brakes, indifferent roads..... 20-25 MPG could be obtained by a good driver cruising around 40 mph.

Today, s driver has NO controls for the engine,other than "cruise" expects to set that to 80 mph and return at least 40 mpg.

These here new-fangled computers, electronic sensors, lean-burn injection technology all have their part to play in this revolution.
The days of pressing your ear to a screwdriver held against the "cly" block and tuning carbs by ear...
ARE LONG GONE. 21st. century engines need 21st. century mechanics. not Otto Daimler wannabes.

ForkTailedDrKiller

22nd Nov 2014, 10:50

Jaba
It may be a little surprise to you but not all Jabas are on on the RAA some are even under VH rego.

Given that the Jabawocky used to own a Plastic Parrot on the VH rego - I very much doubt it! :E

Jabawocky

22nd Nov 2014, 12:52

Jaba

Not so
Long ago you made a statement ( even though you don't know me ) that I didn't have very good trouble shooting skills.
Now you say all these things on how good you are. We'll how good are you. Why don't you come and work with us for a month and see how good you are. No engine enelayis gauges just what the aircraft has feel smell and real knowledge.
No computers to tell you what a wrong.

What you say. You up for it.

Up for it........sure if you pay me to waste my time on you. Because your mindset is one where you can't learn. I am happy to learn from you if you an use logic science and data. :ugh: $175 + GST, plays travel expenses is my going rate. But you need science and data, not "feel, smell and misguided knowledge".

Others, like the the two best engine shops in Australia I work with for free.

More than happy, but are you? I doubt it. Put your money where your mouth is, I do all the time.

LeadSled

22nd Nov 2014, 13:48

Folks,
I hear that Seabird has folded, CASA chalks up another success.
Tootle pip!!

Ornis

22nd Nov 2014, 18:56

https://www.change.org/p/the-hon-warren-truss-mp-cancel-casa-s-proposed-restrictions-on-jabiru-aircraft-engines

"Cancel CASA's proposed restrictions on Jabiru aircraft engines"

Fewer than 600 signed to date.
__________________________

I thought I read somewhere CASA asked Jabiru to voluntarily impose restrictions on operations, but of course I can't find reference now.

Initially Jabiru accepted it had much work to do, but now seem to be arguing students should be able to deal with an engine failure.

That is the judgement CASA must make. Good luck, Lee Ungermann!

Kharon

22nd Nov 2014, 19:22

So much for theory and hope of change then; back to grim reality. Seems the bad habits, aberrations, total disregard for due process, duty of care, procedural fairness, professional ethics and all that old-fashioned stuff, so long abandoned by the McComic tribe are not to be changed.

Forget reforming the regulations; as long has the regulator has the morals of an alley cat no amount of regulatory reform will change anything for the better. The extract below, part of a letter to CASA is yet another excellent example of why the regulator must be reformed. There should be no need for such a letter to have ever been written; never.

Just put the Jab donk issue aside for a moment and read between the lines, and see exactly what the extract is saying.

On 4 November 2014 CASA engaged directly with Jabiru in relation to the proposed restrictions on Jabiru aircraft which included all aircraft manufactured by Jabiru as well as those non-Jabiru aircraft that have a Jabiru powerplant.

In this notice CASA clearly states the following:

“Prior to making the instrument, CASA invites Jabiru to make representations about the terms of the proposed instrument…”

In the days immediately following this Jabiru made arrangements to meet with CASA on 14 November 2014 to address the concerns and to take advantage of the opportunity to discuss the terms of the instrument as outlined in the regulators notice. This meeting was also intended to action CASAs request for Jabiru to respond by 10 November although it should be noted that due to illness of key CASA staff the meeting could not take place by the required date and that CASA agreed to extend the time. At this point Jabiru was led to believe that the proposed instrument would not be published until after the scheduled meeting.

On the afternoon of 13 November CASA pre-empted the outcome of the scheduled meeting with Jabiru and effectively ended the consultation with the manufacturer by publishing the commercially destructive proposed instrument. This occurred some 18 hours prior to the scheduled consultation with Jabiru.

In the days prior to this RA-Aus began receiving enquiries from concerned members noting that CASA officials had made mention of the proposed actions “over a beer or two” during the national Chief Flying Instructor conference held by RA-Aus. The conference is an annual event designed to inform RA-Aus instructors on new developments, changes to rules and generally improve safety in the aviation industry through the provision of training and education. It is fully funded by RA-Aus with no support from CASA or any other public source of funds.

What a sorry testament; yet another perfect snapshot of an ugly scene. That's quite an album on the miniscule's desk, but he won't get to see the pictures; being blinded by the smoke and mirrors of the mystique generator.

Once a good fellah, name o' Barnaby
Decided on aviation harmony;
with a flick of the wrist and an elegant twist,
he delighted a few with his far seeing view and
signed off on the Forsyth review.

Toot toot.

tecman

22nd Nov 2014, 20:58

In the enthusiasm to condemn what may be erratic action by CASA, I'm surprised at how readily the seriousness of the underlying problem has been put aside. First, the high failure rate of Jab engines relative to alternatives has been an open secret for years. And there are many reports on this site and elsewhere of the manufacturer being slow or unwilling to respond to the problem(s). Second, RA Aus has clearly failed to be effective in addressing the issues with the manufacturer, if it ever tried. To compound that, its failure to publish openly detailed comparative statistics added to the obscuration of the engine(s) issues.

The letter from which Kharon quotes is naive and embarrassing. It's heavy on RA Aus commercial self interest and light on addressing legitimate safety concerns about power plants used in aircraft often flown by student pilots and relatively inexperienced recreational pilots. So it's OK to take off with a sub-standard engine because RA Aus students practise forced landings? Give me a break.

You can argue that the CASA process was not ideal, and I might also argue that if I knew all the facts, not just those coming from selected quarters. But with Jabiru unresponsive, and RA Aus ineffective, how long did you expect CASA to sit on its hands?

poteroo

22nd Nov 2014, 21:18

I was one of the CFI's at the RAAus Dubbo conference, and I spoke informally with at least 3 CASA staff. There was never a hint of what was to follow. That's not to say that some people have now 'recollected' comments, and, with the benefit of hindsight, connected the dots. I don't recall the Jabiru engine subject being discussed within the CFI ranks either. happy days,

Kharon

22nd Nov 2014, 21:23

Tecman – I'll concede the point. But you can only work with the information provided. Putting engines aside, I'll agree that the CASA, manufacturer and end user performance has been less than an 'ideal', none providing a timely response to the chronic problems you correctly point out.

However, I wonder, was the regulating culture more open, less threatening and more in the spirit of cooperation; then perhaps the end users, in cooperation with CASA and manufacturers could have produced a more acceptable response for all parties concerned, rather than the current mess which appears to be in the final throes of a death spiral...

Jabawocky

22nd Nov 2014, 21:39

And by what statistical standard are they to be judged against?

Let's look at jets for a minute. Out of several major brands, one of the has to have a higher failure rate than the others. It could well be Rolls Royce if you look at the recent QF years. They might well have had twice the failures in Australia in recent years compared to GE, P&W or CFM.

Now what?:hmm:

I predict if what Kharon has said above is true, that it is game over, before the match is played. The RAAus will be smashed hard as a group of people. The value of aircraft will be decimated. And the OEM will shut up shop. This will break dozens of small business owners. Like drought to farmers there could well be suicides as a result.

CASA should have been careful what they wished for.

I hope I am completely wrong.

Sunfish

22nd Nov 2014, 23:12

Unfortunately jaba you are correct. GA is finished - what is left will either be converted into " mini airlines" if they have the money or give up. Now RAA has been hit for Six by what appears to be a spitefull former employee bent on revenge,

I guess it's the turn of the SAAA next to be destroyed, most probably by not renewing its members exemptions allowing them to conduct their own maintenance. CASA already has had a "trial run" to test the effect of not renewing the exemption, and it was highly effective in preventing flight for a month or so.

Are all ex RAAF people and regulators corrupt assholes? I only have radios and a transponder to buy to finish off, but now I'm starting to wonder if it might be a better use of my time to bin the thing and work on the garden.

Another alternative for the less law abiding might be to go "full feral" - ignore the entire system if they live in sparsely populated areas.

thorn bird

22nd Nov 2014, 23:18

Jabs, why do you imagine CAsA gives a toss

Their job is to regulate, which everyone must agree they do with amazing profusion

If that results in the whole of the aviation industry collapsing,

Stiff.... aint their problem.

Oracle1

22nd Nov 2014, 23:23

In the enthusiasm to condemn what may be erratic action by CASA, I'm surprised at how readily the seriousness of the underlying problem has been put aside. First, the high failure rate of Jab engines relative to alternatives has been an open secret for years. And there are many reports on this site and elsewhere of the manufacturer being slow or unwilling to respond to the problem(s). Second, RA Aus has clearly failed to be effective in addressing the issues with the manufacturer, if it ever tried. To compound that, its failure to publish openly detailed comparative statistics added to the obscuration of the engine(s) issues.

Jabiru is not lily white here I agree and they have had plenty of opportunities to correct the situation, however the cat is out of the bag and CASA et al have stood by and let the situation mushroom for way to long. Where are the figures for Rotax two stroke failures? Shall we ban that engine that was once the mainstay of RAA training? The whole philosophy of recreational flying is doing it cheaper with a different risk profile. CASA should act in the interest of the owners, operators and subcontractors who will lose money, killing Jabiru isn't the answer, trying to cajole them with carrot an stick threats (in private)whilst preserving and improving what structure has been created, should be the preferred tactic. The lack of concrete stats on the subject lies in the regulation shortcomings of both RAA and CASA. There will be plenty of mud about and some of it should stick.

Creampuff

22nd Nov 2014, 23:30

Up for it........sure if you pay me to waste my time on you.C'mon, Jabba, just imagine how comforting it would be to diagnose the cause of engine problems by the mere laying on of hands.

You see, if you've changed a thousand cookd clys, it stands to reason that you will know what caused them to be cookd. No need for no steeeeekin' EGT, CHT, fuel flow, RPM or other data.

If the pilots would just lean it to 25 degrees ROP in the cruise, using that steam driven single point EGT gauge, in accordance with the POH, nothing could possibly go wrong. That's because all those clys are operating at the same point on the EGT curve, at that oh-so-cool ROP setting.

Overheated magneto coil? Just swap the magneto! Once you've swapped a thousand magnetos, you'll know what causes the coils to overheat!

Andy_RR

23rd Nov 2014, 01:21

Tecman, if CAsA, its management and employees were financially damaged by their incompetent handling of this debacle in the same way Jabiru will be then it would be a fair fight but we know that this is far from the case. The bureaucracy will remain long after the industry has been decimated. This isn't a reason for the regulator not to take action, but it is a good reason for them to tread lightly.
Unfortunately regulation has become a national pastime in Australia and many Australians see more need for it than for industry. It will continue to be a self fulfilling prophecy in more than just the sport aviation field unless we change our nation's ways

Sunfish

23rd Nov 2014, 01:29

this is tooo serious to spend time on this ROP/LOP rubbish. Jabiru is going to go out of business and a large chunk of the RAA fleet will go with it.

CASA'a approach to this matter is the classic one - drive them out of business by delay and obfuscation with no hard evidence able to be tested in a court.

Furthermore, I suspect this was timed deliberately to put Skidmore on the spot. He either has to immediately stop this deliberate and lethal assault on RAA or he is tarred with the same brush as McCormick.

To put that another way; "Sir, this is how we have to do things at CASA, it's the LAW Sir, surely you believe in obeying the LAW?"..and Skidmore will neatly fold up, another impotent piece of taxpayer funded windbag.

Radix

23rd Nov 2014, 02:11

............

Creampuff

23rd Nov 2014, 02:50

this is tooo serious to spend time on this ROP/LOP rubbish.Actually, it's centrally relevant to working out what's causing the Jabiru engine failures. Does anyone have a clue where on the lean curve each of the cylinders on a Jabiru engine operates? If not, the analysis of the 'problem' is missing one key variable that drives CHT.

But in the weird and whacky world of aviation in Australia, 'discussions' are generally unhindered by trivialities like facts and cause.

Andy_RR

23rd Nov 2014, 03:58

Creamie, there are at least two aspects of this issue. Firstly are the facts that give rise to the issue and secondly is the fact-free manner in which the issue is being dealt with, despite the regulatory publicity.

Since reputable facts appear to be in short supply regarding Jabiru specifically, the discussion here is more speculation than rational debate. There are plenty of other ROP-LOP threads to reference the basic theory from as well.

As far as an on-line, box-ticking petition goes, if that's what's become of our democracy then we are beyond help.

I have written to my federal MP with this. I may have gone off half-cocked and with crackd clys but I'd encourage everyone with an interest to do likewise.

Here's the guts of my message -

I want to bring to your attention an action by the Civil Aviation Safety Authority that may have grave consequences for a small but internationally successful part of our manufacturing industry - namely Jabiru Aircraft and its affiliated manufacturing entities. Despite being subject to various "tall-poppy" actions and criticisms by some, Jabiru has developed a world-recognized and successful product line in their aircraft and aero engines. Such success doesn't come without failure, miss-step or free from issues that need addressing, but is nevertheless the results of many years of hard work, persistence and personal sacrifice of the many people involved.

Despite this, or perhaps even because of it, CASA has issued and made public a proposal to apply blanket restrictions on the use of Jabiru aircraft and other aircraft powered by Jabiru engines. You can find the relevant proposal published here - http://www.casa.gov.au/wcmswr/_assets/main/newrules/download/spc-cd1425ss.pdf This issue has also been raised on ABC Radio National Breakfast with Fran Kelly - http://mpegmedia.abc.net.au/rn/podcast/2014/11/bst_20141120_0836.mp3

Most concerning is that the CASA proposal is a blanket restriction of all Jabiru products. There is no supporting data supplied or referenced with the proposal that would back such action, nor is it specific to certain models, build dates, serial numbers or any other such identifying detail that people in the aviation industry have come to expect from such airworthiness-related administrative action.

Also, from what I can gather, this proposal seems to have been made public prior to an already scheduled consultation between CASA and Jabiru representatives despite that even the publicity of such a proposal has grave implications for the future of anything Jabiru-related, both current airworthy aircraft and the business itself, locally and overseas.

It might be excusable and dismissed as an administrative error if this were an unprecedented action by CASA, but CASA has made the Friday afternoon "show cause notice" fax the stuff of legend among aircraft operators. Its actions appear to be somewhere between inconsiderate regarding the nature of small business at best and plain commercially vindictive at worst. If the government were to put a broom through the entire organisation of CASA it would find huge support within the industry. Better yet, would be to give CASA a US FAA-style directive to foster and encourage the industry along side the mission to regulate its safety.

Aviation is a vital part of Australia's infrastructure, industry and technological future. In many areas Australian aviation holds a world leading position which the nation desperately needs to maintain for our future prosperity and growth. Heavy-handed and rough-shod regulation will kill it slowly or drive it overseas.

I urge you to bring this issue of the Jabiru regulatory action by CASA to the urgent attention of your government colleagues at the highest level. I also request that you champion a review of the manner in which aviation is regulated in Australia. I look forward to reports of action and hearing of your success in this endeavour.

Mach E Avelli

23rd Nov 2014, 04:04

If this was the big end of town, e.g. an airline suffering premature engine failures, the authorities would impose a reduced overhaul time limit and give the operator x number of hours or y months or even years to get it sorted. Maybe impose additional inspections meantime. But they would hardly dare totally grounding the fleet on the basis of a few failures. Even when Boeing suffered the fatal B737 rudder hardover problems some years back, and the later centre fuel tank explosions in both the 747 and 737, fleets did not get grounded. Procedures and inspections were put in place to mitigate the risk.
Halving a Jabiru engine TBO would have the effect of adding about 15 bucks an hour to the cost spread over the life of the engine. Most owners could absorb that or schools could pass it on to their students without too much pain. Provided reasonable notice to comply was given, of course.
This would be far preferable to the kneejerk reaction of virtually grounding the things without notice.

Ultralights

23rd Nov 2014, 04:13

If that results in the whole of the aviation industry collapsing,

Stiff.... aint their problem.

until the government razor gang starts wondering why CASA has a budget of so much, when the industry they regulate is almost non-existent..

Creampuff

23rd Nov 2014, 04:25

You are preaching to the converted, AndyRR.

I did say, earlier in this thread, that the better approach to this issue would be to ascertain facts and cause...

I was hoping, perhaps as an act of purest optimism, that given the number of these engines that are being run out there, someone in pprune land would have some basic tech data on basic parameters such where the carburettor/induction system is designed and tested to put the cylinders on the lean curve.

The existence of a modification permitting manual leaning suggests that someone is playing with this stuff and may have some useful data.

LeadSled

23rd Nov 2014, 06:21

But in the weird and whacky world of aviation in Australia, 'discussions' are generally unhindered by trivialities like facts and cause.

Ain't that the truth, in spades!!!

Tootle pip!!

Oracle1

23rd Nov 2014, 06:57

I have written to my federal MP with this. I may have gone off half-cocked and with crackd clys but I'd encourage everyone with an interest to do likewise.

Writing to your local LiberalLabor Party MP isn't going to help. They are the problem. Their slavish and corrupt dedication to the principles of globalism, world free trade and lining their own pockets by selling state assets to their mates means they are powerless to enforce honest government. You want to fix this problem then start running campaigns targeting Truss (or his replacement) in his own electorate. Its kill or be killed time. The only letter worth writing to Truss is to tell him to change his dandruff shampoo and that his acting and bull**** skills aren't cutting it. This industry needs to start targeted assaults against any sitting member who wont toe the line. Very simple but our peak bodies are so emasculated we will die while they infight.

Arnold E

23rd Nov 2014, 07:23

Writing to your local LiberalLabor Party MP isn't going to help. They are the problem. Their slavish and corrupt dedication to the principles of globalism, world free trade and lining their own pockets by selling state assets to their mates means they are powerless to enforce honest government

Aint that the truth. :{ Criminals, most of them.

Sunfish

23rd Nov 2014, 07:45

creampuff, it matters not what the cause of the Jabiru failures actually is, still less that there is most likely a solution.

CASA has decided to put Jabiru and the RAA out of business, it matters not what Jabiru say now. All CASA has to do is delay any further discussion until December 25th then Jabiru won't reopen in 2015.

To put it another way nothing that that Barrier, Polar and many others ever meant a thing. Unless its quashed right now Jabiru is finished, to be followed by the experimental fleet in short order.

Ethel the Aardvark

23rd Nov 2014, 08:22

I am a little bit torn,
CASA publish their update with this little snippet 'CASA acknowledges that Jabiru has enjoyed a good reputation for manufacturing safe and reliable engines, and that most Jabiru-manufactured engines continue to operate safely and reliably, in Australia and abroad.'
we all know the quality of a lot of the CASA people involved in this sort of debacle.
however having been involved a little with Jab engines I would not be sending my gran or kids up in a Jab powered aircraft either.
I believe that had Jabiru been a lot more informative over the years with the various defects that have occurred then things might be better now.
I have experienced relatively new cyl heads requiring valves recut due to slight warping, cyl head temp appears very crucial. the leaky induction tubes that have an o-ring and large quantity's of goop probably play a part too. their bottom end appears unbreakable, electric system a bit ho hum.
I wish them luck

triton140

23rd Nov 2014, 08:22

CASA has decided to put Jabiru and the RAA out of business, it matters not what Jabiru say now.

Sunfish is on the money, RAA's fate was sealed with the RPL in Part 61 (aided and abetted by their own failure to implement a robust registration process).

The final nail was CAsA's perception of their inaction on the Jabiru engine "issue", and they played directly into that CAsA perception by their own figures on failures - talk about an own goal. :ugh:

Speaking of own goals, Jabiru themselves have not handled this well. It may well be that they've listened to their customers and fixed the through bolt and valve train issues - but if that's the case, they've communicated it abysmally. :(

It matters not what they say now, but there was a moment in time when they could have captured the high ground .......