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motzartmerv

Jabiru engine make excellent paperweights

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Why the hell don't these things start in the cold??? How bloody long have they had to deal with this problem?? I'm that sick of loosing time and $$ operating these things... If it was a car you would have it towed back to the factory for a refund... Get your sh#%t sorted. Ffs.

 

That Is all.

 

 

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There was a thread on here that I think solved the cold start problem.

 

In the meantime for schools, a blower heater pointing into the engine bay usually solves the problem.

 

 

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Never had a problem since enlarging the idle jet to 1.2mm

 

No choke used since the mod for two winters now

 

A real fix recommend by Jab

 

Phil

 

 

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Never had a problem in 3.5 years and it gets blxxxy cold down here . All mods done to carby as required .

 

Bob

 

 

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" .......... the propellor assembly detached ........ " , what part of the propellor assembly ? , One would have thought that the builder had some responsibility to ensure that the prop. boss was properly torqued , lock wired etc. before fitting the prop , if , in fact this was the part that "detached ". Sounds like a bit of a beat up to me .Typical of the most litigious society on earth , with it's one million lawyers encouraging everybody to sue each other .Don't think Jabiru have too much to worry about .

 

Bob

 

 

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I believe it came away with the prop hub still attached. Can't seem to find an accident report on it.

 

 

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Guest Andys@coffs

Might get very messy, Jabiru engine, ???brand shaft extension, ????nuts bolts washers, orion aircraft, sensinich prop......

 

Try and sort out that mess.....Of course the Orion kit manufacturer if he provides his kit with all those things might be more the point of concentracio, but I suspect they, like most small companies in the aviation industry probably live hand to mouth and thats probably why the shotgun approach in the lawsuit.....

 

Andy

 

 

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Guest Andys@coffs

There are suggestions as to things that can be done to solve the cold starting thing, but of all of those things, which ones can you rely on in a training 24 rego'd aircraft so as to not technically deviate from the LSA certification...... To me, the things you can do are limited to those that J formally publish in an AD.......It would seem to me that playing around with things that might affect LSA certification where your aircraft is used for hire/reward might not be the smartest thing to do ever, and especially at present

 

Andy

 

 

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Jabiru's lawyers said that, as far as the company was concerned regarding this particular engine, its commercial business was complete when it shipped the engine to the distributor. They also said the Australian company never had reason to expect it would end up in Arizona and never did anything to cause it to enter the state.



 

 

 

See above ........... from the article ozzie posted - the law at work ?? - more like the law of deception - could be any aeroplane .............................. BUT I'd say the distributor wouldn't be to happy with Jabiru trying to throw the raw prawn their way

 

 

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I'd say what this is covering is a preliminary step - whether Jabiru has any involvement in the duty of care process.

 

If the case finalises that Arizona do have jurisdiction over Jabiru then there are other matters such as:

 

Did the prop attachment flange part from the crankshaft or not?

 

If it did, did the prop depart cleanly without doing any damage to the control surfaces, or causing any loss of stability and control?

 

If it did then there was an aircraft which needed a routine forced landing fpr which pilots require training.

 

Why the pilot couldn't make that landing and so save the aircraft and his life would then be important and would go up the chain to involve the people who trained and administered him, the legality of the flight at the point the engine failed etc.

 

 

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I'd say what this is covering is a preliminary step - whether Jabiru has any involvement in the duty of care process.If the case finalises that Arizona do have jurisdiction over Jabiru then there are other matters such as:

 

Did the prop attachment flange part from the crankshaft or not?

 

If it did, did the prop depart cleanly without doing any damage to the control surfaces, or causing any loss of stability and control?

 

If it did then there was an aircraft which needed a routine forced landing fpr which pilots require training.

 

Why the pilot couldn't make that landing and so save the aircraft and his life would then be important and would go up the chain to involve the people who trained and administered him, the legality of the flight at the point the engine failed etc.

There are way too many unknowns at the moment.

 

Could it be that a 3rd party suppliers' bearing collapsed, allowing the crankshaft to vibrate causing the crankshaft to snap? Is Jab liable for the QA/QC on all parts supplied to them? Did the propeller detach outside the built structure of the engine (ie mounting flange)? We don't know....

 

Given there has been no published findings (incident investigations) that I could find, it may be well to let this rest rather than speculate on current legal proceedings.

 

 

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The accident report is here.

 

This is the synopsis:

 

While maneuvering adjacent to a private airstrip at a low altitude, witnesses reported observing the propeller assembly separate from the airplane. The pilot maneuvered towards the airstrip and leveled out on runway heading about mid-length of the runway. As the airplane crossed over the end of the runway, it banked to the left and descended into terrain, impacting an open desert field adjacent to several residential homes. Examination of the airplane revealed that the airframe and both wings were structurally damaged. The propeller assembly, including the propeller flange extension were found separated from the engine crankshaft. No further anomalies were noted with the airframe and engine that would have precluded normal operation. The attachment bolts were installed on a painted surface of the propeller flange extension. The paint surrounding this area was flaking away from the surface. Evidence of thread locking material was observed in the threaded areas consistent with installation instructions. Examination of the attachment bolts revealed that four of the six bolts exhibited fracture surfaces consistent with fatigue. One of the four bolts exhibited a multifaceted fracture surface with multiple origins around the circumference. Hardness of this bolt was checked and found to be within the specified hardness range.

The National Transportation Safety Board determines the probable cause(s) of this accident as follows:

 

The insufficient clamping force resulting in a fatigue fracture of the propeller extension attachment bolts and subsequent separation of the propeller assembly in flight. Contributing to the accident was the pilot's failure to maintain sufficient airspeed to avoid an inadvertent stall while maneuvering during the emergency approach to the airport.

And for those that don't read the pdf in the above link the aircraft wasn't a Jab, but an Arion Lightning with a Jab motor of course. It only had done a few hours since completion of the kit. As far as I can tell the kit builder would have been the one that fitted the prop extension that came adrift.

 

 

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I thought the description of the prop to engine connection was way too vague - was the prop flange still welded to the crankshaft or wasn't it.

 

The information implies that the weld let go, but in some ways contradicts that.

 

 

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In my experience a brand new battery helps jabs start good. We had problems til we fitted a new battery and always start the engine cold with full choke and absolutely no throttle. I hate to think I'm telling you to suck eggs andrew but this worked for us.

 

 

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Why the hell don't these things start in the cold???.

Hi Motz,

 

This is the link to Jabs published recommendations for cold starting .... as stated in the attached doc, (most important) make sure the fuel bowl levels are correct and throttle butterfly is closed at start up ... if the throttle is open (even just cracked) the idle and choke system in the carby wont work. I presume you have dne the starter motor earth lead mod as per the starter motor bulletin too??

 

http://www.jabiru.net.au/Manuals/Cold_Start_Checklist.pdf

 

Good luck

 

Vev

 

 

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Never had a problem in 3.5 years and it gets blxxxy cold down here . All mods done to carby as required .Bob

And us aswell. We had an inch of frost covering her at Parkes one morning when we had the 4cyl in her and she started first shot.

 

Iridiums do very well, and even in the 6cyl in her she has no problems.

 

-Linda

 

 

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Yea guys, I've operated 5 jabs over 4 years and I realize some start Ok. And some don't..well versed On jabirus recommendations on how to start the engines.

 

Cherrs

 

 

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On the subject of the prop separation. I don't know wether it's was Jabaru, the US dealers, or whoever fitted the prop that may be to blame here. It does however highlight the fact that the prop is the highest stressed item on the aeroplane, as far as number of forces it is subject to. No 2 is the crankshaft, and they just happen to be joined, on a direct-drive engine.

 

Sounds like the prop-bolts themselves may have been over, or under torqued in this case, (NTSB report) causing failure, which also highlights the dangers of incorrectly torquing prop-bolts, if that is in fact what happened here. Time will tell of course. The general tendenancy by the inexperienced is to overtorque the prop-bolts, which are already stressed in tension during normal operation...............................................Maj...

 

 

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There are suggestions as to things that can be done to solve the cold starting thing, but of all of those things, which ones can you rely on in a training 24 rego'd aircraft so as to not technically deviate from the LSA certification...... To me, the things you can do are limited to those that J formally publish in an AD.......It would seem to me that playing around with things that might affect LSA certification where your aircraft is used for hire/reward might not be the smartest thing to do ever, and especially at present

Andy

Andy, see post # 17 if you referring to my post

 

Phil.

 

 

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On the subject of the prop separation. I don't know wether it's was Jabaru, the US dealers, or whoever fitted the prop that may be to blame here. It does however highlight the fact that the prop is the highest stressed item on the aeroplane, as far as number of forces it is subject to. No 2 is the crankshaft, and they just happen to be joined, on a direct-drive engine.Sounds like the prop-bolts themselves may have been over, or under torqued in this case, (NTSB report) causing failure, which also highlights the dangers of incorrectly torquing prop-bolts, if that is in fact what happened here. The general tendenancy by the inexperienced is to overtorque prop-bolts, which are already stressed in tension during operation...............................................Maj...

Metallurgical analysis would tell in an instant whether this is a Jabiru manufacturing fault or whether Jabiru are completely innocent in this.

 

We just don't have enough of the story.

 

 

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Agree - "insufficient clamping force" responsibility belongs to people other than the engine manufacturer

 

There must be something else for Jabiru to have been dragged into the case though.

 

 

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Ahhh yea.. The quality just oozes. Lost more time yesterday and today due to an intermittent total electrical failure. The engineer pulled the dash out and a handful of wires came out of their crimp locks. Apparently on an entire loom the wires were not crimped, just jammed into the crimpers. Must have been a Friday arvo job.

 

Factory built, 24 rego'd. Can see a couple of jabs entering the market soon..

 

 

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