Jabiru Twin redefining Ugly

[solowflyer]

http://www.jabiru.net.au/images/Jabiru_TwinWhy_South_Africa.pdf

[Diesel Pilot]

I can't stand Jabirus. They're fraught with problems and just about the only aircraft (in the loosest context) that almost comes with a guarantee that you're going to get some sort of emergency or failure. This thing looks like a bad idea from the outset, I'll be looking out for the first crash!

[Mach E Avelli]

I am no fan of the Jabiru airframe and have some reservations about the power plant, even though I fly behind one installed in a Sonex. The Sonex is just one aircraft hit with the ugly stick which performs exceedingly well on low power. So proving an aircraft does not have to be pretty to be effective.

And, despite my reservations about the Jabiru power plant, it is evolving into a reasonably reliable thing.

if this twin gets certified and can be brought to market for under 200 grand, I predict that it will become an all-time best seller.
The potential market is huge.

[Andy_RR]

I think this is a fantastically innovative piece of engineering. It's obviously not conventional thought and it is a bit visually challenging, but it ticks a lot of boxes in terms of twin engined aircraft requirements, including keeping the wing free from nasty nacelles and protuberances.

I'll bet a Mr Bent is doing a merry jig because he can sell twice as many engines to Mr Stiff.

(do you have to have a funny surname to be involved with Jabiru...?)

[T28D]

Wow a plastic Dornier

[Flingwing47]

If the youtube truly IS the first flight, then I reckon the crew need to look at a few good books about test flying.

1. 2 on board
2. Rolling takeoff
3. off centreline
4. early right turn over tiger country
5. no upper air work to check aircraft handling
6. orbit at 500ft on final !!! FFS
7. touch and go off first ever landing

etc etc etc

good luck guys !!:suspect:

[VH-XXX]

If the youtube truly IS the first flight, then I reckon the crew need to look at a few good books about test flying.

It is in South Africa after all! The reason why they wanted a twin was because of the dangers of an out-landing on a farmers property with an AK47 :{


They're fraught with problems and just about the only aircraft (in the
loosest context) that almost comes with a guarantee that you're going to get some sort of emergency or failure.


Engine aside Diesel Pilot, what exactly is wrong with Jabiru aircraft?

I've never heard of any significant issues with a Jabiru yet, engines aside. They have a proven record of passenger protection that likely surpasses most other operating light aircraft in this country. They are economical performers, have an excellent payload, perform very well (model dependant), are inexpensive, are comfortable, have excellent range and these would be some of the reasons why they are arguably the most successful aircraft ever produced in this country.

(do you have to have a funny surname to be involved with Jabiru...?)

Stiff - Bent :D

[Andy_RR]

...what exactly is wrong with Jabiru aircraft?


They are made in Australia ergo they must be bad. This is the way the whole nation thinks... :rolleyes:

[Diesel Pilot]

VH-XXX,

Personally I'm just not a fan. IMO a bit too cheap and nasty, topped off with reliability issues. But hey that's just my opinion, no offence to any proud Jabiru owners/drivers out there :ok:

[VH-XXX]

Ok, I think your initial comments were a tad harsh then.

They're fraught with problems and just about the only aircraft (in the loosest context) that almost comes with a guarantee that you're going to get some sort of emergency or failure.

Doesn't equal:

Personally I'm just not a fan. IMO a bit too cheap and nasty, topped off with reliability issues

[Wally Mk2]

...oh goody a dedicated thread to the ugly duckling 'Jab':E
Donk failures are nasty at ay time but at least with a SE Jab donk failure you know there's no further trying save the day yr on yr way down & try to pick a soft spot for the inevitable. With a twin Jab twice the chance of a failure (as if you needed more chances!) & the added danger of going blw VMCA & spinning in as am sure they'll be jab drivers out there who'll tr to save the day & lose.
I wish the venture well but am reserved:-)



Wmk2

[Andy_RR]

your arguments condemn all twins (except 336/7's) Wally. Nothing special about Jabirus in this regard.

[Wally Mk2]

'Andy' it's the 'jaba' donks that is the issue, as I said 2 of them twice the chance of failure, the airframe is just dog ulgy that's a separate issue more of a personal nature:-) Obviously my ref to the above relates to all twins that are marginal on one donk there's no argument there lots of documented cases of excursions Blw VMCA.
The push-me-pull-me is still scarey losing one on T/off especially the rear, the most efficient one of the two.


Wmk2

[Andy_RR]

Again, all you say is true Wally and for all non-centreline thrust twins, however, I think the Jabiru is a pretty cool solution because:

a) it's started life as a single, so SE climb rate isn't going to be terrible (relatively)

and b) the thrust axes are quite close together compared with most twins, so Vmca is going to be relatively low by comparison.

One would presume that a twin-rating will be needed to fly them still, unlike (I believe) the similar-in-concept Cri Cri.

[tecman]

Wally, I know you'd be disappointed if I didn't, in an entirely predictable fashion, reference a Rotax light-twin option:

Tecnam.com - P2006T (http://tecnam.com/TWIN/P2006T.aspx)

The hand of the venerable Prof. Pascale and the Partenavia lineage is pretty obvious. Never flown a P2006 but my general impression is that he knows how to produce nice-handling aircraft. Guess time will tell how the maintenance, ruggedness etc. stacks up.

[Wally Mk2]

Too true there 'A_rr' but VMCA is a number, it's academic & all relevant as to what it is as going below that number yields the same end result, loss of directional control.
Was shown it in an old Sneca a 100 yrs ago during the endo....bloody scared the crap out of me & reinforced the dangers....ohhhh ahhhhh!

The biggest advantage about any multi eng plane (inc twin jab, barely:E) is you have options & that may mean delaying the inevitable so as to reach a forced Ldg site unattainable in a SE.
I haven't looked closely at the machine but I wonder if it has feathering props?

Wmk2

[VH-XXX]

A J430 is 120 hp at full noise (on a good day). 90hp at 75% power. They will fly on less power of course, loitering along.

This machine has 2 x 85 hp 4 cylinders. She might struggle at full weight if you wanted to climb. I'd imagine they are still testing it so it will be interesting to see what the climb rate is. As a 2 seater it would probably cream it in.

To be offered as an add-on kit for J430's... hmmmmm.... :cool: Name another aircraft you can just "bolt" two engines onto, except that modified Lazair from "The Gods must be crazy" perhaps.

[Andy_RR]

Too true there 'A_rr' but VMCA is a number, it's academic & all relevant as to what it is as going below that number yields the same end result, loss of directional control.
Wmk2

If it's near or below stall speed, then it becomes largely irrelevant. In the case of this Jab, it might be.

If they yawed the engines out a few degrees each, it'd be even less.

[mickjoebill]

1. 2 on board
2. Rolling takeoff
3. off centreline
4. early right turn over tiger country
5. no upper air work to check aircraft handling
6. orbit at 500ft on final !!! FFS
7. touch and go off first ever landing

No helmets, flight suit or gloves and the copilot monitoring his iphone rather than the instruments looks pretty casual.


They have a proven record of passenger protection

What are the statistics on passenger survivability?

If the bottom of the windscreen extended bit lower it would help counter the loss of forward visibility due to the cabin being located behind two engines.

Comments on crash worthiness of having a nosecone instead of an engine up front?
Locating the engines outboard and further from the cabin is a plus?


Mickjoebill

[VH-XXX]

What are the statistics on passenger survivability?

Aside from a well known CFIT, name me a significant injury or fatality in a Jabiru?

I'm not defending them directly, I'm just stating the obvious.

I know a chap that smacked into a power line at VNE during a beat up. Lost the end of his finger and ruptured his eye socket, but he's fine and the aircraft is flying again!

Lowering the windscreen or making the forward parts transparent would be good but you couldn't do it without significant modification which means it would no longer be a bolt on kit.

[Mach E Avelli]

Ahh, the old argument whether a single is safer than a twin.

Give me two engines any day. Even if not the most reliable, the chances of both snuffing it on the one flight (assuming good fuel and enough of it) are remote.

Even if single engine performance results in a slight descent, I like the idea of one remaining power-plant prolonging flight for longer than is the case when a single has a failure. With a legal full load, the old 150 and 160 hp Apaches did not stay aloft very convincingly on one engine, but for all that did not have too bad a safety record.

Pilots will surely kill themselves in this thing, but Charles Darwin would probably have his way with these people eventually anyway.

[VH-XXX]

5. no upper air work to check aircraft handling

What about the single engine handling at the 9m:30s mark where the passenger claps his hands?

[Fred Gassit]

Can't comment on the engines, I've no experience of them but I'm gonna go out on a limb and say I don't think it looks that bad.

[Aussie Bob]

I'll join you on the limb Freddie, so long as you ain't pissed on the tree before I climb it ...

I think it looks pretty cool, Jabbies are great trainers and tough as nails, this little puppy may just make a good twin engined trainer :hmm:

[Arm out the window]

Not a bad concept, just a prick of a position for the engines in that they look like they would cut off all your forward visibility down and to the sides. Apart from that, might be OK if it's got reasonable performance on one and a bit of range.

[VH-XXX]

and a bit of range.

The 4 cylinder Jabs usually sip around 13-15 lph / maybe more. Based on the speeds and RPM on this test flight, around 20lph for the both of them combined might be achievable with circa 135 litres standard in the wet wings. @125 knots perhaps. Probably less fuel than a single 120HP J430.


It's not the first time two Jabiru engines have been used on the same aircraft.... (there's one of these at Tyabb)

http://www.homebuiltairplanes.com/forums/attachments/aircraft-design-aerodynamics-new-technology/21797d1357872804-interest-plansbuilt-lsa-microlight-amphibian-jabiru2200_pelican2.jpg

[Wally Mk2]

Christ is this now a forum for the most ugliest machine to take flight with 2 donks?:) Looks like it's mother got slapped just b4 birth:}
Man really hasn't ventured far since Wilbur & Orville started this whole mess in the looks department:-)


Wmk2

[T28D]

Dornier 28 Sky Servant STOL
http://upload.wikimedia.org/wikipedia/commons/thumb/8/87/Dornier_do_28_d2_sky_01.jpg/800px-Dornier_do_28_d2_sky_01.jpg (http://upload.wikimedia.org/wikipedia/commons/8/87/Dornier_do_28_d2_sky_01.jpg)

[Mach E Avelli]

From all accounts, that Dornier was a good machine, let down somewhat by poor (American) engines.
Now, if Jabiru offer a tail-wheel version of their fugly twin, what a great combination for training it would be. Teach pilots proper ground handling and the basics of twin flying all in one package.

[rutan around]

If you are tired of looking at ugly have a squiz at this:

http://www.aopa.org/-/media/Images/AOPA/Home/News/All%20News/2012/August/Velocitys%20V%20Twin/120830vtwin-top.jpg?w=640&h=329&as=1 (http://www.aopa.org/News-and-Video/All-News/2012/August/29/Velocitys-V-Twin)

[Wanderin_dave]

How about a fixed gear, fixed pitch twin with gear and pitch controls? Ain't she a beauty! :yuk:
The Lancer. the Light Twin that Wasn?t | Aircraft Market Place (http://www.acmp.com/blog/the-lancer-the-light-twin-that-wasnt.html)

[kingRB]

hahaha thanks for that link WD :ok:

Always enjoy finding yet another aircraft type I never knew existed. An interesting heap of **** ;)

[aroa]

in the eye of the beholder.
IMO it looks cheeky and spiffy.

Well done those Seff Efriken guys, Rod and others ...who looked well outside the box for a terrific and simple solution to a complex problem. :ok:

I admit some concern at the "test flight" style...but there you go, worked well for them.

May the new Jabbajabba prosper.!! :ok:

[NOSIGN]

The Gods must be crazy anyone?

[VH-XXX]

NOSIGN The Gods must be crazy anyone?

Refer to my post #17 :ok:

To be offered as an add-on kit for J430's... hmmmmm.... Name another aircraft you can just "bolt" two engines onto, except that modified Lazair from "The Gods must be crazy" perhaps.

For those that haven't seen this "classic" movie, do yourself a favour.

[Wally Mk2]

Just on a side note here as the word 'ugly' can only be described so much b4 it becomes known fact (see twin Jaba for EG) & the story ends:)

I wonder who'd be brave (or stupid enuf) to do what young Ryan has done recently (fly round the globe solo) in a Jabiru..................now that person if they survived would be a hero of magnanimous proportions:}
Ryan's recent result shows that the Yanks can build some pretty reliable brutal donks!:-)


Wmk2

[aroa]

Do it in a Jabiru...why not. Been done in a Victa 115*, AA Trainer 100? and other assorted 'smallies' J Johansson's global jaunts spent huge amounts of time over water,too.
With the Jab, route planning would be the prob re range, I guess. Might have to circumvent the Pacific via Kamkatcha and Alaska.

NO GPS and all the goodies either in the 'good old days" and I can attest that clock, compass, map, ruler and pencil still works.

*If I remember his story correctly, the Victa got shipped Japan to Canada.

And the AA guy Tholstrup? had just got his PPL in it, and off he went !

Bravo all those of adventurous bent.!:ok:

Now who will lend me a Jabby...and a bucket of $$$s:ok:

[Wally Mk2]

'aroa' yes it has been done in small planes but what power plant was up front of them? NOT a jaba donk that's 4 sure, that's where the 'bloody brave' part comes in, the jaba airframe is just ugly, doesn't mean it wouldn't make the trip other than perhaps scaring off the natives in far flung countries!:}:E

Flying around the world these days is no big deal anymore, there's a long list of 'Earthrounders' seems as long as you have the funding, a slight shift of yr "cheese on yr crackers" & yr off!:-)


Wmk2

[27/09]

If I remember his story correctly, the Victa got shipped Japan to Canada. That only happened because the Russians wouldn't give him permission to land to refuel at Petropavlosk on the way from Japan to the Aleutian Islands

[VH-XXX]

The look of the Jab twin was growing on me until I re-watched the video and spotted the rear of the engine cowls with the big gaping hole. Looks a bit untidy. Some re-designed streamline engine cowls would go a long way to enhancing the beauty.

Just thinking about $$. A Rotax 914 which is required to power a J430 including required CSU is approximately $40k plus fitting. This kit should retail at around $35k plus labour at a rough guess.

[NOSIGN]

Sorry XXX, I missed that you beat me to it. Good blokes must think alike.

[VH-XXX]

Sorry XXX, I missed that you beat me to it.

Oh that's ok, it's not a competition :ok:

Good blokes must think alike.


Touche

[outlandishoutlanding]

Aside from a well known CFIT, name me a significant injury or fatality in a Jabiru?

Katoomba last week.

[ranmar850]

Aaawww, it's cute. I think it was designed by someone from Pixar, one of the characters for a cartoon called "Planes" , the aerial equivilant of "Cars":ok:

[Squawk7700]

Last week (or possibly the week before that), the first Australian built Jabiru twin took flight in Bundaberg. Coming to an airport near you!

[rutan around]

A few weeks ago I was in Bundy and was fortunate enough to watch some of the Jab Twin test flights and afterwards talk to the test pilot. (Much more enjoyable than destroying a perfectly good aircraft to comply with SIDS to solve some data free non existent problem whilst bleeding dollars by the thousand)
The pilot said flying on one engine was a pretty benign event and over the nose visibility was good as the slope of the nose was just a continuation of the windscreen slope. The engines are attached to each end of a canard (nothing wrong with canards :E ) and the canard is bolted to the firewall where the engine would be if it was a single so it's pretty easy to keep the CofG where you want it. The twin is in Bundy for testing and modification as required. Cowls and vertical stab were to have some attention. I loved the short engine control runs from the cockpit. I reckon if one fell off you could just reach out and operate the engine by hand.
The reason the Jab was modified to be a twin by a Mineral Exploration Company in Africa wasn't due to stroppy farmers toting AK 47's . It was because after a successful forced landing of one of their planes it cost the company millions in ransom money to get their pilots back. They figured it would be cheaper to develop a twin than to risk paying more ransom money. ( This would never happen in Australia. It would be cheaper to pay the ransom money.:{)
Cheers RA

[Stanwell]

rutan around,
On the subject of canards..

"The best place for a canard is on someone else's aircraft".
(Roy Braybrook, Former Chief Project Engineer, BAe)

[Jetjr]

Its an upgrade to standard 4 seat Jabiru
Same nose wheel weights as current single
160hp vs 120hp from 6 cyl, going to run at max speeds pretty easily
More complicated than the single 6 cyl but a neat way to get a twin.

[aroa]

Stani,
Braybrooks comment rates with some General saying " I can see no military use for aircraft, they'll just frighten the horses" :mad:

And the rest is history

[cattletruck]

They coulda made it a tri-motor as there is still room up front, or even shoved one on the tail like the trilander and have 4 motors all up....just in case 3 of 'em fail at once.

[Squawk7700]

https://www.youtube.com/results?search_query=OTOSHSOQ

:ok:

OTOSHSOQ

[LeadSled]

Folks,
I think it is a rather nice looking little aircraft, I first saw the original quite some time ago, the idea is not new.
Sad they have to do it is SA, because Australia/CASA makes it too hard.
Tootle

[Jetjr]

Theres one in RSA and the one in video is in Bundy but personally built and owned to keep CASA happy

[Ultralights]

https://www.youtube.com/results?search_query=OTOSHSOQ

:ok:

OTOSHSOQ

Relax on the stick a bit..

[Squawk7700]

Relax on the stick a bit..

I did hear somewhere that some of the airframe components needed some tuning after the flight as you probably could have guessed from the control movements. Something was amiss as the South African variant showed no such signs in the video assuming that the first flight video was actually the first flight.

Who better than to have at the controls than Jamie the owner. Undoubtedly the most experienced test pilot in this country and I'll qualify that by saying that he would have test flown more brand new aircraft than all of us combined.

[Jetjr]

500kg aircraft, hot day in bundy, pretty normal stick activity id reckon

[Harryg]

I can't stand Jabirus. They're fraught with problems and just about the only aircraft (in the loosest context) that almost comes with a guarantee that you're going to get some sort of emergency or failure. This thing looks like a bad idea from the outset, I'll be looking out for the first crash!

I suppose you've never owned one. I've owned one since 2008 and have never had a problem and I'm not in the minority. I have only ever used according to the operators manual and maintenance schedule.

[pistonpuffer]

It looks like the Jabiru TWIN has passed all the hoops and is now a certified aircraft in South Africa.
I understand single engine performance is as required for twins but have not seen official figures ( and that is for fixed propeller !).

Re jab engines, time to put some things to rest. The second generation ( ie the first hydraulic lifter ) had issues, oddly enough only seen in flying schools at sea level. After long investigation found due to crank case resonance from the lifters that when added to thermal cycling gave premature wear to thru bolts.
Solved in the third generation ( and also in second generation engines upgraded to third generation specs ).
The reliability of the third generation seems on a large number of hours accumulated significantly better than Rotax.
Fourth generation engines have just started production ( early 2017)

[Jetjr]

Theres been plenty of problems in other versions of Jab engines. Problem is far from at rest. Nothing solved for the thousands of owners out there.
There isnt even a clear break between generatons, just slow on line changes.
They are good value and cheap to maintain. Perform well for the weight and are simple design
Latest models are major changes, having lost their main engine part manufacturer, will need many hours in the field before claiming anything.

[MakeItHappenCaptain]

Engine aside Diesel Pilot, what exactly is wrong with Jabiru aircraft?

The fuselage stands up quite well. Has to. The engines keep letting go...:E

[Ultralights]

as i have said before, the last aircraft you want to fly over tiger country with is a Jabiru, If you have an engine failure over tiger country, the best aircraft to be in would be a jabiru.

[5179]

"ulltralight"...with respect, that's a load of rubbish. ( the last aircraft you want to fly over...bla bla bla )

I've accumulated over 500 trouble free hrs zig zaging ALL OVER this country, serious tiger country EVERYWHERE. Apart from GA, the only other aircrafts i bump into are......yea, you guessed it.......jabs.

Serviced right, treated right, they are damn great. Excellent cruisers, good room, comfy, well mannered, great endurance, after sales great, cheap to maintain.

Yes......a few had issues, but the other 99% no problems at all. The ones that did BTW, were in the main "trainers"....getting flogged hr after hr.

[Squawk7700]

Yes......a few had issues, but the other 99% no problems at all.

LOL, get off the grass! (And I don't mean the grass runway)

[5179]

I won't prolong this discussion ( easy too btw ) .....it was revealed in the "breakdown / analasys " of the engine faults .....that running out of fuel was deemed "an engine malfunction"........now get your head around that. ( no more fuel to burn.......engine defect )
There were other CRAZY reasons that were labelled engine faults, it beggers belief that casa got away with pure rubbish on this jabiru engine matter.
I'm not denying there were some serious design flaws, that factory were addressing ( through bolts, dropping valves, flywheel bolts, to name the 3 main probs ) These flaws have been addressed, and feed back is now good.
Repeating......my 500+ hrs in a jab, have been trouble free.

[Arm out the window]

Further on the twin, I wonder what the stall is like - just looking at it, I would think that once a rate of descent built up it would want to pitch up with all that surface area ahead of the wing, and maybe be a bit hard to get the nose back down? Could be totally wrong of course!

[Jetjr]

Weight and balance pretty much the same as single 6 cylinder. Pretty hard to stuff up w&b and benign stall
In RSA they rin 750 kg MTOW, so pretty useful aircraft as a twin

How has Jabiru solved valve seizure and guide problems?
Who says other problems solved?
A whole lot of Jabiru problems for owners dont relate to engine failure but early overhaul or repairs found in maintenance.
Casa action was designed to make Jabiru wake up, only hurt existing owners, Jabiru now have regulator imposed restrictions on everyone (inc experimental) who doesnt implement their major upgrades or replacements

[Gearup3reds]

Never been a fan of the Jabi's no matter what design, gotta say though this thing looks like a Dorneir D28 ate a pallet of marshmallows and gave birth to the Fisher Price version of itself!! And agree with video comments, very rugged around the edges for so-called "test pilots"....of sorts! I dunno much about their engines in particular but to me they just sound like they want to quit, or maybe it's all the rattles and plastic gadgets trembling on the airframe. Definitely not the twin for this black duck!

[horizon flyer]

It looks like the little Cri Cri twin and all the early Jab engine problems makes it sounds like a Lycoming 360 it has most of these problems except they don't fix the design faults just blame the pilot for bad operation, so at least Jab are fixing them on their engines.

[Acrosport II]

https://www.youtube.com/results?search_query=OTOSHSOQ

http://cdn.pprune.org/images/smilies/thumbs.gif


I'm surprised how much aileron control movement was used during climb-out, with so little response from the aircraft.

[pistonpuffer]

No, the reliability of 3rd gen engines, and 2nd gen upgraded to 3rd gen specs, is very very good. These engines have accumulated a huge number of hours, enough to give very high statistical probabilities, and it is really looking better than Rotax.
There was a good article by Rick Frith and a second article by another author in the same online issue of RAA magazine, I think it was around May 2016 (dont hold me to that ) that sets it all out. Give that a read.

[pistonpuffer]

500kg aircraft, hot day in bundy, pretty normal stick activity id reckon

I think that is Jamie's style

[Squawk7700]

You can hide anything with a splash of colour :-)

http://members.iinet.net.au/~bc75/twin.jpg

[5179]

I think that is Jamie's style

think you'll find that this is all being done out of RSA.....not Oz

[Squawk7700]

Not quite...

There's one in Sth Africa and Jamie has one he owns personally at Bundy.