Flying over square
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John Deakin - Pelican Perch. Very clever, intelligent and insightful commentator, mixed with a fair modicum of emotive and dubious anecdotes and nonsense .
Read his spray on the Whyalla report.
CASA got it wrong, Lycoming don't know what they're talking about, Continental don't understand their own engines and the FAA is lost in space.
Reminds me of revivalist pastor selling enlightenment to the one true religion.
A lot of what he says is good, and a lot of it is rubbish. Problem is trying to work out which one is which.
Read his spray on the Whyalla report.
CASA got it wrong, Lycoming don't know what they're talking about, Continental don't understand their own engines and the FAA is lost in space.
Reminds me of revivalist pastor selling enlightenment to the one true religion.
A lot of what he says is good, and a lot of it is rubbish. Problem is trying to work out which one is which.
STABLISATION of temperatures is as important as total temperature. Hot spots need to be reduced. Overcooling will stuff an engine quicker than quick heating!
Oil temp is part of the problem as well as turbo RPM.
Oil temp is part of the problem as well as turbo RPM.
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Oil temp , now that is a real red herring, the oil temp in my T28 stays at 70 C long after shutdown, in fact I use the temp to pump the oil back out of the sump to the oil tank 30 minutes after shut down.
Anyone who thinks Deakin is some sort of aviation engine witch is not someone I would let fly any of my aircraft, he is really one of the true guru's and was quite correct in the case of the Whyalla Accident as the ATSB finally recognised in the amended report.
Anyone who thinks Deakin is some sort of aviation engine witch is not someone I would let fly any of my aircraft, he is really one of the true guru's and was quite correct in the case of the Whyalla Accident as the ATSB finally recognised in the amended report.
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ohhh dear.........hear I go again, agreeing 100% with T28D 
I flew in a Lancair IV today Turbo IO-550 330HP, owner needs a dose of JD too, just old instructors from 20 years ago I guess. He will start seeing the light
BSD........you are kidding me right
So mr guru, start with a really good list of where JD gets it so wrong, I can't wait.
That statement sounds like the sort you get from people who have never built engines, run them on Dyno's nor run them with all cylinder monitors and played around experimenting. As an engineer, who has done a fair bit of all of the above, i may not be a George Brayly, as much as I wish I knew even what he has forgotten, but I can sure tell you everything these guys talk about I have proven.
So spill ya guts buddy, I am keen to be enlightened.
J
I flew in a Lancair IV today Turbo IO-550 330HP, owner needs a dose of JD too, just old instructors from 20 years ago I guess. He will start seeing the light
A lot of what he says is good, and a lot of it is rubbish. Problem is trying to work out which one is which.
So mr guru, start with a really good list of where JD gets it so wrong, I can't wait.
That statement sounds like the sort you get from people who have never built engines, run them on Dyno's nor run them with all cylinder monitors and played around experimenting. As an engineer, who has done a fair bit of all of the above, i may not be a George Brayly, as much as I wish I knew even what he has forgotten, but I can sure tell you everything these guys talk about I have proven.
So spill ya guts buddy, I am keen to be enlightened.
J
T28,
your oil temp stays at 70C?
I reckon your oil temp sender is near the oil tank, IN the turbo while it is glowing red the oil will be much hotter. That is why a slow cooldown [not a really long idle period] is needed to allow some time for temps [turbo, cylinder, crankcase, oil] to stabilise.
Yep, 30 mins after stopping the oil will still be quite warm.
Engines like being heated and cooled - slowly. [but I am sure I am preaching to the converted]
your oil temp stays at 70C?
I reckon your oil temp sender is near the oil tank, IN the turbo while it is glowing red the oil will be much hotter. That is why a slow cooldown [not a really long idle period] is needed to allow some time for temps [turbo, cylinder, crankcase, oil] to stabilise.
Yep, 30 mins after stopping the oil will still be quite warm.
Engines like being heated and cooled - slowly. [but I am sure I am preaching to the converted]
So once again, Clinton, are you advocating immediate shutdowns, according to your understanding of the objective data?
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Dear Guru Jabawocky, I am really not fussed about your engine prowess, good luck to you.
Personally I have enjoyed reading most of JD's Pelican's Perch.
A couple of quickies for you though GJ, quoting JD
DOH
A bit like when he forgot to dangle the 747 dunlops into LA. DOH x2
No JD there's not just 2 types of pilots, there's 3. There is also those that never have and never will.
Whyalla
Getting a bit emotive with that one too. For better or worse the aircraft was fitted with the instruments that it was fitted with.
He's a clever cookie, but I doubt he's the mesiah.
I'm sure you could care for as little of what I think as I do for you, but you did ask.
Personally I have enjoyed reading most of JD's Pelican's Perch.
A couple of quickies for you though GJ, quoting JD
There is also the perception that running a tank dry scares passengers. Maybe, but I don't think so. I've done it many times with all types of passengers watching…
A bit like when he forgot to dangle the 747 dunlops into LA. DOH x2
No JD there's not just 2 types of pilots, there's 3. There is also those that never have and never will.
Whyalla
In my opinion, the primary cause of this accident was CASA's failure to require, and the operator's failure to install and use, proper engine instruments that monitor the EGT and CHT of ALL cylinders, as the JPI EDM-700 and 800 do.
He's a clever cookie, but I doubt he's the mesiah.
I'm sure you could care for as little of what I think as I do for you, but you did ask.
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Well I am sure there will be a whole heap of comments on these but I'll bite first.
1. Running the tank dry.....no big deal.......I can get accrurate data to change tanks when about 2 litres is left, but if you want to know you squeezed every drop out of a tank, why not. heck if you do not want to no biggie either.
If thats your biggest beef....ohh dear!
2. Forgetting to dangle thy dunlops, well he is a big enough man to tell the story and write about it in public, but lets get the facts straight.....he did not guts it did he.....went through a scan of things and got back on top of his game. Are you casting the first stone?
3. Whyalla prang...... if you read all the reports and thought about it objectively, you can see his comments about the ATSB report and more importantly how the operator ran those engines, you might give Deakin and Brayly a bit more credit.
4. Actually I care a whole heap more than you think. I am still amazed, is this the best you can find?
PS: If you have read all JD's articles you will also note that some written over 10 years back have had updates inserted and noted as over the following years, mainly through GB's test stand and the APS development they all learned a few finer points in a few areas. I am sure you will have seen these. Its all in the test data, and it is amazing how they can convince my data logs to look like they say they would. Poured over 10 hours of data log tonight, just to be sure
MIHC
Did you read Jamairs post #69. Happened to be flying behind a Turbo 550 today....what happens with that machine, even discussed this with the owner.....as per post #69
1. Running the tank dry.....no big deal.......I can get accrurate data to change tanks when about 2 litres is left, but if you want to know you squeezed every drop out of a tank, why not. heck if you do not want to no biggie either.
If thats your biggest beef....ohh dear!
2. Forgetting to dangle thy dunlops, well he is a big enough man to tell the story and write about it in public, but lets get the facts straight.....he did not guts it did he.....went through a scan of things and got back on top of his game. Are you casting the first stone?
3. Whyalla prang...... if you read all the reports and thought about it objectively, you can see his comments about the ATSB report and more importantly how the operator ran those engines, you might give Deakin and Brayly a bit more credit.
4. Actually I care a whole heap more than you think. I am still amazed, is this the best you can find?
PS: If you have read all JD's articles you will also note that some written over 10 years back have had updates inserted and noted as over the following years, mainly through GB's test stand and the APS development they all learned a few finer points in a few areas. I am sure you will have seen these. Its all in the test data, and it is amazing how they can convince my data logs to look like they say they would. Poured over 10 hours of data log tonight, just to be sure
MIHC
Did you read Jamairs post #69. Happened to be flying behind a Turbo 550 today....what happens with that machine, even discussed this with the owner.....as per post #69
Last edited by Jabawocky; 15th Oct 2011 at 12:28.
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Actually, BSD, if you had read the article about dangling the Dunlops properly, if at all, you would have realised that the approach was at San Francisco.
There is also another factor that you need to realise about the Whyalla crash. Since the PA31-350 was released, with its POH that recommended leaning in climb, there has been an octane rating change in the fuel. If you follow the POH there is a very good chance you will have several cylinders in detonation. However, the POH was never changed despite this change. I wonder how many operators still lean?
There is something like $70k a piece on a PA31 wing that gobbles Avgas like its going out of style. It amazes me that the majority of owners don't fit all-cylinder monitors and GAMI injectors. Their maintenance costs and running expenses would be so much lower as to cover the installation costs time over time. The only downside is having to educate the pilots being turned out mouthing OWT about engine management. Perhaps its all too hard for some to understand, the generation that just wants to be told the figures where to run the engine day in and day out despite varying mission profiles and environment.
There is also another factor that you need to realise about the Whyalla crash. Since the PA31-350 was released, with its POH that recommended leaning in climb, there has been an octane rating change in the fuel. If you follow the POH there is a very good chance you will have several cylinders in detonation. However, the POH was never changed despite this change. I wonder how many operators still lean?
There is something like $70k a piece on a PA31 wing that gobbles Avgas like its going out of style. It amazes me that the majority of owners don't fit all-cylinder monitors and GAMI injectors. Their maintenance costs and running expenses would be so much lower as to cover the installation costs time over time. The only downside is having to educate the pilots being turned out mouthing OWT about engine management. Perhaps its all too hard for some to understand, the generation that just wants to be told the figures where to run the engine day in and day out despite varying mission profiles and environment.
there has been an octane rating change in the fuel.
Would you care to elucidate on that one. The ASTM standard has not changed as far as octane is concerned for 100/130. 115/145 ceased to be available years ago.
100LL has less TEL in it now, but with higher octane base stock, the effective octane is the same, even though we have sadly lost some of the be benefits of higher TEL fraction.
CASA got it wrong, Lycoming don't know what they're talking about
Actually, you left out ATSB, otherwise a fairly accurate summary. Have you actually read the Coroners report??
A number of claims in the original ATSB report were chemical and physical impossibilities.
What some of you dim sods don't seem to realise is that running "high RPM, low boost" as the norm is all a bit new, and the suggestion that you wouldn't run an engine "low RPM, high boost" would really raise an eyebrow from those who learned their trade when big pistons ruled the roost.
It is interesting to read a Lycoming engine manual from the '50's/60's, (or Continental) versus "newer" editions, to realise that even the manufacturers are short on "corporate memory", and the lawyers reign supreme.
Sadly, the most common method of leaning I hear around clubs and schools actually maximizes the threat of detonation.
Tootle pip!!
Last edited by LeadSled; 15th Oct 2011 at 14:55.
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PLovett, I apologise as you are correct SFO it was for the event mentioned. Perhaps I got it wrong because when I read things like
AH no JD, you've forgotten 'Landing Flaps' as well or the gear warning horn would be screaming its head off.
Take a few more points off JD because you still don't have Landing Flaps.
OK now we have the Landing Flap, that's when you do the landing checklist.
OFTEN 200,000lbs heavier? It's possible. Anyone who's flown a 747 knows about inertia and how the 747 handles at extremes of weight. I personally have found the opposite of what JD says to be the case re inertia, but then I don't profess to have all the answers.
Did he say?
Well JD the gear warning horn would have come on when the flaps extended beyond (memory is fading here) 23 degrees??? and there is nothing you could have done to silence it.
All this is a long winded way of getting around to say that (just like Geoffrey Thomas's reports on the Qantas PIA's of late) the good parts of the message get lost when you know parts of the story are bullsh!t.
Passing about 1,300 feet, I glanced around the cockpit: All was well, right side showed the same thing as the left, guy in the right seat was awake, gear handle was off, speed brakes/spoilers were armed ... yup, all set. Watching my instruments, I got a funny little feeling. Gear handle off? Off? Why is it OFF? It's not supposed to be off, it's supposed to be Down. It felt like someone dumped a bucket of ice water down my back. I had forgotten the gear, and the landing checklist!
The only points I'll give myself that night are that I didn't flinch, or look. I just said very quietly, "Gear down, please, and landing check."
. Four men simultaneously sucked in their breath. And four men watched as the gear handle went down, the green lights came on, and red light went off as the doors closed. I called for the final flaps, the checklist was completed passing 1,000 feet, and the landing was uneventful.
What about all the safety devices? Landing gear warning horn? Well, cargo airplanes are often very heavy on landing -- 200,000 pounds or more heavier than passenger flights. Normally, the thrust levers can be reduced to idle when the wheels are still 50 feet off the runway, but with that much extra weight, the 747 tends to crunch the landing if you do that, so most of us kept some thrust until well into the flare. I would have done that, that night, and the warning horn would have been too late to do anything about it.
Did he say?
I would have done that, that night, and the warning horn would have been too late to do anything about it.
All this is a long winded way of getting around to say that (just like Geoffrey Thomas's reports on the Qantas PIA's of late) the good parts of the message get lost when you know parts of the story are bullsh!t.
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Leads led
You can say that again!
And as for leaning the chieftain engines, it's not that complex or hard once you have a small amount of knowledge. Unfortunately very few if any CPL students get any.
Sadly, the most common method of leaning I hear around clubs and schools actually maximizes the threat of detonation.
And as for leaning the chieftain engines, it's not that complex or hard once you have a small amount of knowledge. Unfortunately very few if any CPL students get any.
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Whyalla
Quote:
In my opinion, the primary cause of this accident was CASA's failure to require, and the operator's failure to install and use, proper engine instruments that monitor the EGT and CHT of ALL cylinders, as the JPI EDM-700 and 800 do.
Getting a bit emotive with that one too. For better or worse the aircraft was fitted with the instruments that it was fitted with.
Quote:
In my opinion, the primary cause of this accident was CASA's failure to require, and the operator's failure to install and use, proper engine instruments that monitor the EGT and CHT of ALL cylinders, as the JPI EDM-700 and 800 do.
Getting a bit emotive with that one too. For better or worse the aircraft was fitted with the instruments that it was fitted with.
You're joking right? Have you seen how inaccurate the old analog gauges are?
The Whyalla report noted that the company climb power setting and fuel flow. Consider what would be happening to the engine if the old FF gauges (which really arn't fuel flow) were slightly over reading as well. Id say 100/L /engine at climb is no where near enough FF.
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Turbo cool down periods?
Really?
no
SERIOUSLY!!...
So lets examine your 'cool down'
You taxi in. Come to a stop and set 1000 RPM and wait 3-5 minutes, then shut down. Are you bothering to monitor your engine instruments and watch what is happening? Nope, most do this without any thought, and are too busy gathering up all their maps, putting headsets in bags etc and preparing to depart the aeroplane.
Lets examine 'immediate shutdown'
You land, and taxi back to your parking bay. Normally what 800-1000 RPM. ?? any more than that and your going to ride the brakes. So your trip back to parking takes what 3-5 minutes?
So please tell me, how much cooler the turbo is going to be if i taxi in and wait another couple of minutes at 1000 RPM????
Cheers
Jas
Really?
no
SERIOUSLY!!...
So lets examine your 'cool down'
You taxi in. Come to a stop and set 1000 RPM and wait 3-5 minutes, then shut down. Are you bothering to monitor your engine instruments and watch what is happening? Nope, most do this without any thought, and are too busy gathering up all their maps, putting headsets in bags etc and preparing to depart the aeroplane.
Lets examine 'immediate shutdown'
You land, and taxi back to your parking bay. Normally what 800-1000 RPM. ?? any more than that and your going to ride the brakes. So your trip back to parking takes what 3-5 minutes?
So please tell me, how much cooler the turbo is going to be if i taxi in and wait another couple of minutes at 1000 RPM????
Cheers
Jas
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Jas, why don't you call the agents for Honeywell and Garrett turbochargers and ask them?
For my area of interest in turbochargers (Rajay), they say this
as
Reprinted with permission from Aircraft Maintenance Technology, October 1997.
I think I'll stick with that rather than the advice of the savants of an anonymous internet bulletin board.
Kelly Aerospace Power Systems
1404 E. South Blvd.
Montgomery, AL 36116
(334) 286-8551
(334) 286-1992 Fax
1404 E. South Blvd.
Montgomery, AL 36116
(334) 286-8551
(334) 286-1992 Fax
Allowing a cooling down period for the turbo is a maintenance procedure that should be universally practiced. When taxiing in, allow the engine an additional two minutes of idle time before going to ICO. This simple practice will prevent any oil residue from coking in the hot turbine housing and will prolong the life of the turbo.
Reprinted with permission from Aircraft Maintenance Technology, October 1997.
I think I'll stick with that rather than the advice of the savants of an anonymous internet bulletin board.
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Thankfully the savants seem to have more experience on blown enjine handling than one named after a RR hair dryer.
The taxi is more than enough to stabilise temp and clear oil after a well planned minimum power approach by an experienced pilot who can do it without wild power gyrations, by the time one is at the bay the engine (s) will have been cooling gradually for some 8 minutes in the descent/approach/ taxi.
More than enough "turbo run down time" by any standard.
Perhaps one should read the Garrett treatise on turbo handling for ALL internal combustion engines.
??? should we let the TPE 331 idle for 2 minutes after on blocks as well, it has oil and bearings, personally I shut them down ASAP less noise for the ground people and saves fuel, BTW it doesn't hurt the engine.
The taxi is more than enough to stabilise temp and clear oil after a well planned minimum power approach by an experienced pilot who can do it without wild power gyrations, by the time one is at the bay the engine (s) will have been cooling gradually for some 8 minutes in the descent/approach/ taxi.
More than enough "turbo run down time" by any standard.
Perhaps one should read the Garrett treatise on turbo handling for ALL internal combustion engines.
??? should we let the TPE 331 idle for 2 minutes after on blocks as well, it has oil and bearings, personally I shut them down ASAP less noise for the ground people and saves fuel, BTW it doesn't hurt the engine.
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Darling trent 
What a wonderfully written piece of advice this is... An additional 2 mintues to the taxi time. HOW long was the taxi time? is it 5 minutes? 2 minutes?
Lets see. YCEM rwy 17. 3 minutes to taxi to parking + 2 minutes 'cool down' yep that works.
YCEM rwy 35. 30 seconds to taxi to parking +2 minutes 'cool down' I can see how well that fits into rayjay's explanation
YMMB rwy 13. about 8 minutes to taxi back....do you really need the extra 2 minutes?
What oil residue? ah you mean the oil that is getting past the oil rings and being blown into the turbo via the exhaust. hmm So we are worried about that sticking to the gizzards. Well in that case we are better off having the turbo hot as hell so it can burn off. The longer we run the thing at low power, the more 'residue' can enter the gizards, and being cool, it is going to stick.
Sitting between the hairdryers as you do, you'd be more aware than us mere plebs on how fast temperatures stabilise. Once stabilised, it ain't going to get any cooler running it for an extra 2 minutes or full hour.
You miss the whole fact, that I am not saying immediate shut down is acceptable. I am saying that after a reasonable taxi time, the turbo WILL be cool enough for shutdown upon parking. I.e ycem's rwy 35 would see me run the engine for probably 2 minutes before shutdown because I thought about it.
Jas
Allowing a cooling down period for the turbo is a maintenance procedure that should be universally practiced. When taxiing in, allow the engine an additional two minutes of idle time before going to ICO.
Lets see. YCEM rwy 17. 3 minutes to taxi to parking + 2 minutes 'cool down' yep that works.
YCEM rwy 35. 30 seconds to taxi to parking +2 minutes 'cool down' I can see how well that fits into rayjay's explanation
YMMB rwy 13. about 8 minutes to taxi back....do you really need the extra 2 minutes?
This simple practice will prevent any oil residue from coking in the hot turbine housing and will prolong the life of the turbo.
Sitting between the hairdryers as you do, you'd be more aware than us mere plebs on how fast temperatures stabilise. Once stabilised, it ain't going to get any cooler running it for an extra 2 minutes or full hour.
You miss the whole fact, that I am not saying immediate shut down is acceptable. I am saying that after a reasonable taxi time, the turbo WILL be cool enough for shutdown upon parking. I.e ycem's rwy 35 would see me run the engine for probably 2 minutes before shutdown because I thought about it.
Jas