Two more Jabirus down
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Two more Jabirus down
It appears that the Jabiru curse has struck again, Two more Jabirus down in Queensland within 4 days. It's lucky they make a good crashworthy frame! - they need it, with the regularity of those engine failures!
What was it Jack Ranga said in another thread? - "If you want a Jabiru, just buy a paddock, there's a Jabiru engine in most paddocks!"
Plane makes emergency landing in Victoria Point paddock
Pilot uninjured in emergency landing at Parkinson
What was it Jack Ranga said in another thread? - "If you want a Jabiru, just buy a paddock, there's a Jabiru engine in most paddocks!"
Plane makes emergency landing in Victoria Point paddock
Pilot uninjured in emergency landing at Parkinson
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717tech - I'd hazard a WAG that the second Jabiru landed in a paddock with trees at the far end of it! If he'd landed fully in that solidly-wooded country behind the aircraft, that Jabiru wouldn't look any near as pretty as it does now! - and we'd probably be reading about another light aircraft fatality!
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Shame about 7984, that does at lot of flying around AF.
ABC news reported that it collected a barb-wired fence around its undercarriage on the way in - good thing it stayed right way up.
Hopefully it will be in the air again soon.
ABC news reported that it collected a barb-wired fence around its undercarriage on the way in - good thing it stayed right way up.
Hopefully it will be in the air again soon.
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Probably why the ATSB are now conducting investigations like this
Research investigation into the reliability of light sport aeroplane engines
Most people probably would never air their true thoughts on a public
Forum about such incidents as this, I feel for fear of litigation.
Part of the problem for the ATSB is a lot of failures go unreported, plus
They don't tend To focus as much on recreational aircraft.
Research investigation into the reliability of light sport aeroplane engines
Most people probably would never air their true thoughts on a public
Forum about such incidents as this, I feel for fear of litigation.
Part of the problem for the ATSB is a lot of failures go unreported, plus
They don't tend To focus as much on recreational aircraft.
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Quote:
Pilot was probably wondering what happened to his oil temperature and pressure...
Pilot was probably wondering what happened to his oil temperature and pressure...
I can tell him! The first went up and the second went down!
(By the way this one was not the famous "catastrophic" engine failure, this one was shut down before it got to that)
There is an AD on Jabbies to replace the landing gear bolts every 500 hours. Perhaps this person forgot? It is an AD that you wuld ignore at your peril!
Or as an afternote perhaps this person was a contributing factor in the AD
Or as an afternote perhaps this person was a contributing factor in the AD
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The Jab undercarriage bolts had a size upgrade some years back (eg An4 to An5 or similar. Replacing them at 500 hours isn't so bad, $30 worth of bolts and nuts and maybe an hours work so not a big deal.
Locking up a main wheel under braking (causing skipping) is a major contributor to losing the undercarriage. It's the reason why the Vans RV 12 kits were recently modified as owners locking up the brakes were causing skipping and subsequent bending around where the undercarriage attaches.
So Aairbatic, I don't believe you would need to be concerned about the Jabiru undercarriage in general. There's a video on the front page of their website that shows the undercarriage during certification drop tests, very impressive!
PS: I may happen to own one :-)
Thanks Wally, I assume you don't want a ride then?
Oh that's right, not enough engines :-) !!
Locking up a main wheel under braking (causing skipping) is a major contributor to losing the undercarriage. It's the reason why the Vans RV 12 kits were recently modified as owners locking up the brakes were causing skipping and subsequent bending around where the undercarriage attaches.
So Aairbatic, I don't believe you would need to be concerned about the Jabiru undercarriage in general. There's a video on the front page of their website that shows the undercarriage during certification drop tests, very impressive!
PS: I may happen to own one :-)
Thanks Wally, I assume you don't want a ride then?
Oh that's right, not enough engines :-) !!
Last edited by VH-XXX; 26th Aug 2013 at 11:02.
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There's at least one very unhappy Jabiru "crash-test-dummy" out there, who has instigated a sizeable website, asking a lot of questions about Jabirus that he wants answers to. I can't see him getting them.
Because the website owner hasn't indicated any recent updates to his website (and it appears a lot of his info is 4 to 12 yrs old), a lot of the info there may not be particularly relevant at this present time.
JabiruCrash.com - the story of my flight (and plane crash) in a Jabiru aircraft with Ron Bertram (deceased) - jabiru engine failure, Jabiru piston failure, ultralight
Another item I found that is probably of great relevance and interest to Jabiru engine owners, is this following blokes claim that all factory Jabirus have their pistons installed backwards.
Jabiru have installed their pistons backwards
As it appears the Jabiru merely uses standard Holden pistons, I'd be concerned about the fact they're being used - rather than aviation-specific pistons - or tailored pistons.
I can recall a story from a bloke who worked on the Holden engine factory assembly line, from many years ago, telling me how Holdens had three markings for pistons as they lobbed in the basket for checking prior to installation. These markings were dobs of green, yellow and red paint.
The pistons that met all specifications precisely (including weight, a critical factor) were dobbed with green paint. These pistons went into export engines only.
The pistons that met specifications with a shove, went into "domestic production" engines. These pistons could have flaws in machining or casting, that were not deemed to affect engine life seriously.
Then came the final group of pistons, those marked with red. These pistons hovered between "just usable" and bordered on the, "to be scrapped" range - due to being so far outside specifications, it was dubious as to whether they would produce a full engine life.
I was advised these pistons were duly installed in the engines of fleet purchase or rental vehicles, and Govt vehicles.
Because the website owner hasn't indicated any recent updates to his website (and it appears a lot of his info is 4 to 12 yrs old), a lot of the info there may not be particularly relevant at this present time.
JabiruCrash.com - the story of my flight (and plane crash) in a Jabiru aircraft with Ron Bertram (deceased) - jabiru engine failure, Jabiru piston failure, ultralight
Another item I found that is probably of great relevance and interest to Jabiru engine owners, is this following blokes claim that all factory Jabirus have their pistons installed backwards.
Jabiru have installed their pistons backwards
As it appears the Jabiru merely uses standard Holden pistons, I'd be concerned about the fact they're being used - rather than aviation-specific pistons - or tailored pistons.
I can recall a story from a bloke who worked on the Holden engine factory assembly line, from many years ago, telling me how Holdens had three markings for pistons as they lobbed in the basket for checking prior to installation. These markings were dobs of green, yellow and red paint.
The pistons that met all specifications precisely (including weight, a critical factor) were dobbed with green paint. These pistons went into export engines only.
The pistons that met specifications with a shove, went into "domestic production" engines. These pistons could have flaws in machining or casting, that were not deemed to affect engine life seriously.
Then came the final group of pistons, those marked with red. These pistons hovered between "just usable" and bordered on the, "to be scrapped" range - due to being so far outside specifications, it was dubious as to whether they would produce a full engine life.
I was advised these pistons were duly installed in the engines of fleet purchase or rental vehicles, and Govt vehicles.
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I've read that Jabiru Crash in detail and there are a lot of allegations and a lot of mud being thrown in the hope that some of it will stick. Not just at Jabiru but even at the guy maintainting it and questioning of his credentials (now deceased after Bankstown crash).
Long story short, the aircraft suffered an engine failure into a wooded area.
The first page of the Jabiru flight manual mentions to fly the aircraft at all times as if the engine could fail at any time. It's good advice
As for the pistons, Jabiru's answer is that they are the other way around because the rotation of the Jabiru engine is opposite to that of the Holden Commodore. They are not actually Holden pistons, they are "like" Holden pistons and they are modified from the supplier to suit the Jabiru engine.
Likewise, the Rotax 912 has 100% interchangeable rockers with the Ford Falcon
Long story short, the aircraft suffered an engine failure into a wooded area.
The first page of the Jabiru flight manual mentions to fly the aircraft at all times as if the engine could fail at any time. It's good advice
As for the pistons, Jabiru's answer is that they are the other way around because the rotation of the Jabiru engine is opposite to that of the Holden Commodore. They are not actually Holden pistons, they are "like" Holden pistons and they are modified from the supplier to suit the Jabiru engine.
Likewise, the Rotax 912 has 100% interchangeable rockers with the Ford Falcon
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Onetrack,
I'm surprised that someone of your age believes this nonsense-
Is this the same guy that worked for Mobil and helped suppress the engine that ran on water and later worked in a Condom factory where they put a pin hole in every 100th condom?
Before further efforts a made to ruin the reputation of a small Australian company perhaps you should acquire some knowledge on the subject.
This is shamelessly lifted from an article on modifying Holden engines:-
Cheers RA
I'm surprised that someone of your age believes this nonsense-
I can recall a story from a bloke who worked on the Holden engine factory assembly line, from many years ago, telling me how Holdens had three markings--------
Before further efforts a made to ruin the reputation of a small Australian company perhaps you should acquire some knowledge on the subject.
This is shamelessly lifted from an article on modifying Holden engines:-
The majority of stock replacement type pistons have the gudgeon pin offset by about 0.060". The only reason for this is to reduce the tendency for the piston to slap after a cold start - the slight imbalance created by offsetting the pin makes the piston rock over relatively gently at TDC instead of "slapping" laterally from one side to the other. The amount of offset isn't great enough to have a material effect on performance, but despite this there is a persistent old wives tale to the effect that installing this type of pistons backwards will result in a power gain. If you remember any high school trigonometry (or you have a crank position vs. piston position vs. rod angle spreadsheet) you'll soon be able to work out that the small offset will have a negligible effect on rod angularity and piston thrust loads. And if you factor in the slight relocation of true TDC from reversing the pistons then the effect is even smaller. If you want to put the slugs in backwards go right ahead, you won't hurt anything. But don't expect the output to increase by any measurable amount. Of course all this only applies to stock style pistons - performance or racing pistons generally have zero offset.