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Jabiru limitations


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Hi geoffreywy, I will take a punt here , that cracked barrel , I reckon it was on the oil filter side of the engine, could you let me know also which side your bolts broke and wether top or bottom, the indications I get is that it is top bolts on oil filter side, bottom bolts on other side, same with barrels, most common. this is not caused by detonation !.A.D

What is your opinion or official cause ?

 

 

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What is your opinion or official cause ?

Hi Camel, I do have a very strong opinion on the cause. IT is not caused by detonation, I'm very sure of this , have a good look at this engine, the breakages and their location line up exactly with another problem within the engine ,cylinder for cylinder . Its a geometrical problem , which is easy to fix, within reason .

I have data involving 12 bolts so far. I read a lot on this site regarding through bolt issues , so I would appreciate some more data from those unfortunate owners that have had broken bolts /cylinder's etc.

 

I need to know , side that failure occurred and if on the top or bottom ie oil filter side ,l/h , or , other side , r/h, top or bottom for which side . with the extra data I should be in a position to give a more accurate and detailed reasoning. However .... forget about detonation as being the primary reason , I know detonation doesn't help , anywhere! . I have looked at several engines and can see no sign of detonation , I 'm not saying that it doesn't happen.... as it can with any engine given the right conditions . Even if detonation was present at the time ... its not the primary cause.

 

Any more data re bolts please..... would be appreciated!.

 

A.D.

 

 

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Hi Camel, I do have a very strong opinion on the cause. IT is not caused by detonation, I'm very sure of this , have a good look at this engine, the breakages and their location line up exactly with another problem within the engine ,cylinder for cylinder . Its a geometrical problem , which is easy to fix, within reason .I have data involving 12 bolts so far. I read a lot on this site regarding through bolt issues , so I would appreciate some more data from those unfortunate owners that have had broken bolts /cylinder's etc.

I need to know , side that failure occurred and if on the top or bottom ie oil filter side ,l/h , or , other side , r/h, top or bottom for which side . with the extra data I should be in a position to give a more accurate and detailed reasoning. However .... forget about detonation as being the primary reason , I know detonation doesn't help , anywhere! . I have looked at several engines and can see no sign of detonation , I 'm not saying that it doesn't happen.... as it can with any engine given the right conditions . Even if detonation was present at the time ... its not the primary cause.

 

Any more data re bolts please..... would be appreciated!.

 

A.D.

Appreciate your answer, do you share info with anyone I.e Jabiru, Camit or CASA that can do something about this. I personally have always felt it was the way the case halves join and heating different material i.e. alloy case and steel cylinders.

 

Why are you researching this? Do you have a way of getting Jabiru to listen to you ?

 

 

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Appreciate your answer, do you share info with anyone I.e Jabiru, Camit or CASA that can do something about this. I personally have always felt it was the way the case halves join and heating different material i.e. alloy case and steel cylinders. Why are you researching this? Do you have a way of getting Jabiru to listen to you ?

The standard Jabiru case joining technique can be a contributing issue if it hasn't been done correctly; CAMit use a different technique entirely. The gudgeon pin offset question is well-known and CAMit uses the opposite offset, as does, I believe, Jabiru S.A. I believe that both Lycoming and Continental use aluminium cases with steel barrels.

 

 

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Gee this is a great way to spend Christmas Day. Our beloved Jabs seem to have a very clouded future. Just a quick question on the Instrument...Does it apply to ALL Jabiru engines? I have a VH registered, Experimantal catagory Jabiru (J430) and the pilot has a PPL.

 

 

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Dear Dmech. Yes the barrel crack was on the oil filter side, the bolt broke top front l/h side...

Hi geoffreywh, Thanks for info ,we sorted out some problems 3 yrs ago with a number of jabs within our club here in W.A., and these have been running very well since. Its just recently since I have started to assemble my own engine , and this casa intervention , that I decided to research the bolt situation ,which I have read as being a random occurrence . but looks like it isn't at all , there seems to be a definite pattern, which looks like its directly linked to the problems we sorted out 3 yrs ago, possibly why we have not had any bolt issues .

I'm still working on this , so would appreciate hearing of any bolt failures.

 

Thank's A.D.

 

 

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Appreciate your answer, do you share info with anyone I.e Jabiru, Camit or CASA that can do something about this. I personally have always felt it was the way the case halves join and heating different material i.e. alloy case and steel cylinders. Why are you researching this? Do you have a way of getting Jabiru to listen to you ?

I did contact jab back in JAN.2012 and talked to Rod Stiff , however got the same treatment that everyone else seems to get , he stated that they sorted all the problems and had to go flying . I left all my contact details , but never heard from him or anyone else from jab since . I have talked to Ian Bent at Camit, on several occasions , [much better person to talk to] and I can say that their engine is a much better engine , and I would be surprised if they have the same through bolt issues that are experienced on jab engines.

The case halves and bolt structure on both engines, is still very fragile , in my opinion . In my spare time , I've started to design another crank case , which wont be split will still have through bolts ,so that all other jab parts can be used, there could be a slight increase in weight , but then as improvements to jab engine and .CAE. are gradually increasing the weight anyway , I don't think that's going to be a problem .

 

I have manufactured my own longer barrels and con rods , which are ready to go .

 

I've been researching this engine since I started flying behind one 4 yrs ago j160 . I was fortunate to be able to buy the eng. out of this plane after engine stopped dead in the air after a circlip /piston issue.

 

for a reasonable price , but after I discovered the main problem with these engines . Up until then I hadn't seen inside of these engines , except on utube .

 

I made up a model which demonstrates what is going on in the engine , I'm sure if you were able to see this model , you would be convinced , as has every one else that has seen it . I was recently asked to demonstrate it at the Serpentine aero club [ jab members] which was well received .

 

I posted in the jabiru aircraft engines problem solving thread JAN 2012 almost 3 yrs ago

 

No I cant think of away of getting jab .to listen to me . Hopefully /perhaps through this forum it might happen. I've also posted on the zenith forum, on this matter 2 yrs ago as well.

 

Still need some numbers on the through bolts!!

 

All the best for Christmas [ whats left of it] and more peace and confidence in flying the jab next year

 

A.D.

 

 

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Appreciate your answer, do you share info with anyone I.e Jabiru, Camit or CASA that can do something about this. I personally have always felt it was the way the case halves join and heating different material i.e. alloy case and steel cylinders. Why are you researching this? Do you have a way of getting Jabiru to listen to you ?

With out prejudice.

also to add to your question info sharing , JAN2012 a senior member of our club contacted casa and ASTB, as far as I know he didn't get a reply. I have contacted casa and Repcon recently and they have acknowledged my email , and have requested my permission to send my email complete to their or casa investigation team , so at the moment I feel I cant say to much, but will, after Repcon have finished with it.

 

 

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Guest Maj Millard
I did contact jab back in JAN.2012 and talked to Rod Stiff , however got the same treatment that everyone else seems to get , he stated that they sorted all the problems and had to go flying . I left all my contact details , but never heard from him or anyone else from jab since . I have talked to Ian Bent at Camit, on several occasions , [much better person to talk to] and I can say that their engine is a much better engine , and I would be surprised if they have the same through bolt issues that are experienced on jab engines.The case halves and bolt structure on both engines, is still very fragile , in my opinion . In my spare time , I've started to design another crank case , which wont be split will still have through bolts ,so that all other jab parts can be used, there could be a slight increase in weight , but then as improvements to jab engine and .CAE. are gradually increasing the weight anyway , I don't think that's going to be a problem .

I have manufactured my own longer barrels and con rods , which are ready to go .

 

I've been researching this engine since I started flying behind one 4 yrs ago j160 . I was fortunate to be able to buy the eng. out of this plane after engine stopped dead in the air after a circlip /piston issue.

 

for a reasonable price , but after I discovered the main problem with these engines . Up until then I hadn't seen inside of these engines , except on utube .

 

I made up a model which demonstrates what is going on in the engine , I'm sure if you were able to see this model , you would be convinced , as has every one else that has seen it . I was recently asked to demonstrate it at the Serpentine aero club [ jab members] which was well received .

 

I posted in the jabiru aircraft engines problem solving thread JAN 2012 almost 3 yrs ago

 

No I cant think of away of getting jab .to listen to me . Hopefully /perhaps through this forum it might happen. I've also posted on the zenith forum, on this matter 2 yrs ago as well.

 

Still need some numbers on the through bolts!!

 

All the best for Christmas [ whats left of it] and more peace and confidence in flying the jab next year

 

A.D.

Dmech......very interesting. I have been suggesting that the weaknesses in the crankcase itself is at the basis of the problems for some years now. The cases need to be structurally more stiffer and internally supported better in places. Everything hangs or rotates in this ( hot) alloy case. Most other aero engines use forged or cast alloy cases for better strength and thermal stability.

 

 

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Sounds good dmech, but if your having to use new case, cylinders and rods, isnt a whole new engine?I thought you had fixed some existing engine problems?

What was done?

Hi jetjr , The new case is for a future engine, rods and barrels as well , but I can use the new rods and barrels on my existing case. existing engine can be modified easily to be reliable , as we have already done back in early 2013.

 

 

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I feel deja vu when I read this.

I received a optimistic from somebody, funny. I since I have virtually read the same post on more than one occasion, especially the CAMIT AND JAB SHOULD BE IN A JOINT VENTURE

 

 

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My CH701 has a Jabiru 2200 engine, thus far (a whole 5 hrs) it is performing nicely. Passenger carrying is not a worry until I have flown off the 25hr test period. Will CASA have resolved the issue by then? I doubt it! Have to say that I will fly it like I fly any light aircraft, with an awareness of surrounding forced landing area possibilities! A lot of things I don't understand, why are 2 pilots considered safer than 1 pilot plus passenger? Why, in a VH registered experimental where I am already obliged to have a placard in front of the passenger warning them will I then also have to have them read and sign a waiver? Why could I build and instal my own automotive engine conversion without having to warn passengers? and finally, why with all of the difficulties, the expense and the bureaucracy involved in aviation do we bother? I thought part of CASA's brief was to encourage aviation but in fact they are probably the biggest single impediment to general aviation in this country.

 

 

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Unfortunately, it is actually NOT part of CASA's 'mission statement' to 'encourage aviation': (my bolding here)

 

To enhance and promote aviation safety through effective regulation and by encouraging the wider aviation community to embrace and deliver higher standards of safety.

 

Of course, these are just weasel words, as is the case with just about all such statements from almost any organisation. ''Aviation Safety' is as nebulous a concept as the Platonic 'Good', and recognition of what is - and is not- 'good' is a societal judgement; since CASA is a society of and to itself alone, it is little wonder that it was found by the 'Truss' review to be comprehensively in need of being bought in touch with the rest of the world..

 

But Wait - There's More!. According to CASA:

 

We act at all times with fairness and integrity. We maintain the highest levels of professionalism and act with high ethical standards and without bias.

 

 

 

We make balanced judgements which are risk based and evidence driven. We act innovatively and with flexibility to meet our responsibilities.

 

And if you believe THAT, then you would also happily await the awakening of your Norwegian Blue from its sad repose, pining for the fjiords.

 

 

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Did readers know the CASA "proposal" is now "alive", from 23rd December, and it is rather difficult to find. The CASA website front page info only takes you to the old draft.

 

Here is the real deal: http://www.comlaw.gov.au/Details/F2014L01806 I have not compared it to the draft. I'd be surprised if they are the same.

 

Congrats to CASA for successfully hiding another vital bulletin. Now THAT's innovation!

 

Have flying schools operating at populated tower zones (eg MB etc) or the ATC tower staff there, been directly notified by CASA? Mmmmmmmm. Doubt it.

 

 

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