Jabiru limitations

[alf jessup]

jetr,

 

Rotax have almost 10 times the amount of 912's flying worldwide compared to jabiru,

 

So yes they may have the same failure rate as Jab currently, but you put 50,000 Jabiru engines out there and then make a comparison,

 

Rotax is far more sturdy and reliable than your Jabiru engine, and if you can't see that your dreaming

 

 

[AVOCET]

Ive woken up three times today and im still dreaming ?

 

 

[AVOCET]

Ive woken up three times today and im still dreaming ?

 

 

[AVOCET]

Ive woken up three times today and im still dreaming ?

 

 

[alf jessup]

Ive woken up three times today and im still dreaming ?

It's all a bad dream Mike, some one told me its 2015, huh??? only a few years ago it was the millenium

 

 

[facthunter]

I don't understand that Alf. Surely the rate is just that... So many per unit. Why would equalling the numbers sold alter the rate?

 

I've never said the Rotax isn't a more reliable engine, but it's also heavier and liquid cooled, more expensive to purchase and for parts and will get more so if the dollar falls more. In a jabiru it will require weight in the TAIL to be added. Can't we get past the Jab BAD talk.? What if Rotax suddenly stopped making motors? Would we all stop flying? In the overall picture the concentration on the Jab is getting out of reality.

 

Both engines use a carburetter which has suss fuel floats, and no guaranteed replacement is available. Have we heard much about that? Nev

 

 

[dazza 38]

Ive woken up three times today and im still dreaming ?

No you have Tourettes.

 

 

[alf jessup]

I don't understand that Alf. Surely the rate is just that... So many per unit. Why would equalling the numbers sold alter the rate?I've never said the Rotax isn't a more reliable engine, but it's also heavier and liquid cooled, more expensive to purchase and for parts and will get more so if the dollar falls more. In a jabiru it will require weight in the TAIL to be added. Can't we get past the Jab BAD talk.? What if Rotax suddenly stopped making motors? Would we all stop flying? In the overall picture the concentration on the Jab is getting out of reality.

Both engines use a carburetter which has suss fuel floats, and no guaranteed replacement is available. Have we heard much about that? Nev

Nev,

 

The Bing carburettor is quite common actually, was used on the BMW motorcycles before fuel injection, Rotax also has 2 carbs feeding 2 pots so I am gathering a far better fuel distribution than the other.

 

The only reason Rotax would stop building engines was if they continually delivered a sub standard product & the public revolted against them (can't see that happening in the near future)

 

I want Jab to be successful don't get me wrong.

 

Alf

 

 

[Oscar]

In the end, due to insufficient incontrovertible data, the matter of Jabiru engine reliability becomes a matter of judgement. CASA has made a judgement. I agree with it. You don't. We both own and fly a Jabiru. I put a CAE in mine, you put your family in yours...

Ornis, I (and I think many Jab. engine owners) agree that the numbers do not show that Jab. engines are equally as reliable as Rotax - certainly Rotax 912's. For that exact reason, we have also added most of the CAMit mods. to our 2200 and will be further upgrading it to 'full' CAE specs. in the near future (barrels and heads, once test flying of other mods that have been done to our aircraft is complete and we have, in particular, extensively revised the cooling arrangements and proven them by test flying). Once that is done, we confidently expect to have an engine that will, with due attention to all of the factors relevant to good engine management, provide us with reliability that is every bit as good as Rotax, even if it may require more routine maintenance.

 

As you have said, CASA 'made a judgement'. The major bone of contention here - and the real subject of this thread - is whether that judgement and the resultant action by CASA:

 

a) was based on reliable data that had been properly analysed; and

 

b) represents an appropriate response to the 'situation'.

 

I'm not sure what your opinion is on a); you clearly believe that in the case of b) it was appropriate. The only people outside CASA who have actually seen the CASA data are a few members of the RAA Board - and they are unequivocal that they consider the answer to both a) and b), is NO. Until such time as CASA makes the data publicly available for review - and as we know, CASA has so far refused all requests to do that, which I believe raises serious questions about the transparency and fairness of the action - we have only the CASA judgement on one hand and the assessment by the RAA Board members who have seen it on the other, by which to be guided.

 

Therefore, we out 'here' who can only look on from the outside, can equally only make 'judgements' on judgements. We do not have the information by which to make any judgement from facts, other than those such as the ATSB and the RAA incident reports - and in both cases, there remains a real and significant question as to the rigour of any analysis that has/may have been undertaken.

 

That Rotax 912 engines are far more tolerant of a wider range of operating conditions than are Jabiru engines, I don't believe is in any way in issue. The form of Rotax 912s is without doubt, inherently more tolerant: water-cooled heads are, quite simply, protected far better than air-cooled heads and a great deal of the operating tolerance of Rotax 912s flows from that: tolerance to variations in fuel quality, a more consistent cooling installation in all operating conditions, almost no occurrence of thermal shock. All of that is good; there is an inevitable price to be paid, and that is reflected not just in direct purchase and operating cost but also in the weight penalty and the effect that has on the rest of the 'system' - especially airframe robustness - that makes up an aircraft. However, those issues are not part of this debate.

 

Jabiru engines are without question, far less tolerant of 'out of condition' engine management and I presume (since I don't know, as I have zero interest in Rotax engines) also of proper maintenance. They are also far less tolerant of fuel quality issues. Despite the at times almost comically ignorant utterances of some self-proclaimed 'expert' commentators regarding some of the design/ manufacturing /metallurgical features of Jabiru engines, the 'scatter factor' between operational experience indicates pretty conclusively that engine management is a major factor in getting satisfactory life and reliability from Jabiru engines.

 

We have FTFs with histories of repeated early-life engine failures / incidents, and FTFs that report thousands of trouble-free hours on engines that came off the same production line. Since the engine is a common factor, one has to look at the 'uncommon' factors - operation and maintenance (and to a lesser degree, installation). There is a lot of ground to cover there and it isn't appropriate to the core discussion of this thread; suffice it to say here that there is quite enough evidence of disparity in the patterns of reliability experience between various operators to suggest that serious investigation needs to be undertaken to determine what significant differences there are in operation and maintenance and how that affects reliability.

 

That said, it remains a fact that Jabiru engines are at the 'fragile' end of the air-cooled aero engine spectrum and that they certainly have 'weak links' that can too easily be broken unless scrupulous attention is paid to their operation and maintenance - and yes, I agree that Rotax 912s are more tolerant, by a fair margin. CAMit improvements are designed to improve the reliability of the basic Jabiru engine design by addressing each 'weak link', based on research and development and testing. I agree entirely with those who say that Jabiru should achieve that same thing, and that Jabiru management are being obdurate in not so doing.

 

Once CAE engines have passed both of JAR 22H certification and ASTM certified testing, Jabiru could - if it wished and had the sense to so do - commence to deliver engines for LSA 24-reg, 24 'C' reg, and 95.55 reg Jabirus and bypass the CASA injunction completely. The necessary testing is an expensive business; to do the 'full 9-yards' of both standards, the cost is likely to be of the order of $500K or possibly more and take several months. However, both the necessary facility and the expertise exist. If CASA were willing to be co-operative rather than obstructive, the time and cost could be somewhat shaved; however the standards are explicit and must be met.

 

The hurdles to be jumped through for an engine manufacturer are extensive. It is worth noting that - as far as I am aware - the only certificated /certified engines that are realistic propositions for 'light sport' aircraft are the Rotax 912, the Continental 0200D, and the Jabirus. Neither Ul Power nor d-Motor are certificated / certified - at least according to their websites as of today. You could put them in your 19-reg Jabiru, or equally, put in a CAE engine and save a lot of money, but they are NOT candidates for 24 'C'-reg, 24 'D'-reg or 95.55 reg. Nor will they ever be in their current form under the existing standards, because they rely on EFI for achieving performance. So far, only Rotax has done the very, very extensive work required to get an EFI system that meets the standards. Rotax has a US$9B annual turnover company behind it - and as we know, the 912 iSc has not been without problems!

 

So - while there are potential solutions available to meet the 'problems' nominated by CASA as the reason for its action, it is in no way as simple as 'just do 'X', FFS, and all this would go away'. There is no silver bullet.

 

And the question still remains: is the CASA action appropriate to and justified by the unreviewed and withheld data it claims validates the action? Why are not certain aircraft that have known and documented structural / aerodynamic /occupant safety deficiencies that have and do kill people not been subject to the same sort of limitation? If it is OK to slap a limitation on one manufacturer on the basis of 'probability' - that has not resulted in a corresponding spate of statistics of that 'potential' being realised in 25 years of operation - why has CASA not also similarly acted where there are known and documented problems?

 

 

[jetjr]

As far as Rotax stopping production, i wouldnt expect it to happen due to performance. A single large legal claim could stop it overnight. The bigger the company, the larger the target for litigation if something goes wrong.

 

Insurers look at potential company worth when deciding to make a damages claim.

 

BRP would drop aviation in a second if it felt there was a serious avenue or maybe a precedent for claim against it. Far bigger than BRP have almost sunk due to potential litigation from a small section of its business and they all are highly risk averse as a result.

 

Doubt its a big part of their business, so must remain highly profitable and risk free to continue.

 

Interesting how 3300 is involved in the limitations based upon comparisons with Rotax when there is no 120hp option to compare it to. It may in fact be one of the the safest 120 hp aviation engine in Australia!!!

 

I never said Jabiru were more reliable, quite the opposite, but the ATSB report is quite clear about FAILURES..............INCIDENTS is a different story.

 

When some start talking injury to ground observers, actual engine outs landings are the only way this happens. So far the only data we have says this happens the same in each.

 

Casual readers could easily think all Rotax dont fail as often as any Jabiru. Dangerous thoughts.

 

As with most debates truth isnt at either end of spectrum

 

 

[facthunter]

Oscar. To your last proposition The CASA is a bureaucracy that REACTS rather than examines. and analyses It has a record of doing this and often a lot of unnecessary damage is done.. It gets into a position where it doesn't want to lose face so behaves intractably. A fall guy usually is found when needed. They don't get volunteers often for this so it must be a happy place to work. Oft quoted " they are so confused at head office, they are running around stabbing each other in the chest". I know many who have worked there. Nev

 

 

[AVOCET]

Ornis, I (and I think many Jab. engine owners) agree that the numbers do not show that Jab. engines are equally as reliable as Rotax - certainly Rotax 912's. For that exact reason, we have also added most of the CAMit mods. to our 2200 and will be further upgrading it to 'full' CAE specs. in the near future (barrels and heads, once test flying of other mods that have been done to our aircraft is complete and we have, in particular, extensively revised the cooling arrangements and proven them by test flying). Once that is done, we confidently expect to have an engine that will, with due attention to all of the factors relevant to good engine management, provide us with reliability that is every bit as good as Rotax, even if it may require more routine maintenance.As you have said, CASA 'made a judgement'. The major bone of contention here - and the real subject of this thread - is whether that judgement and the resultant action by CASA:

 

a) was based on reliable data that had been properly analysed; and

 

b) represents an appropriate response to the 'situation'.

 

I'm not sure what your opinion is on a); you clearly believe that in the case of b) it was appropriate. The only people outside CASA who have actually seen the CASA data are a few members of the RAA Board - and they are unequivocal that they consider the answer to both a) and b), is NO. Until such time as CASA makes the data publicly available for review - and as we know, CASA has so far refused all requests to do that, which I believe raises serious questions about the transparency and fairness of the action - we have only the CASA judgement on one hand and the assessment by the RAA Board members who have seen it on the other, by which to be guided.

 

Therefore, we out 'here' who can only look on from the outside, can equally only make 'judgements' on judgements. We do not have the information by which to make any judgement from facts, other than those such as the ATSB and the RAA incident reports - and in both cases, there remains a real and significant question as to the rigour of any analysis that has/may have been undertaken.

 

That Rotax 912 engines are far more tolerant of a wider range of operating conditions than are Jabiru engines, I don't believe is in any way in issue. The form of Rotax 912s is without doubt, inherently more tolerant: water-cooled heads are, quite simply, protected far better than air-cooled heads and a great deal of the operating tolerance of Rotax 912s flows from that: tolerance to variations in fuel quality, a more consistent cooling installation in all operating conditions, almost no occurrence of thermal shock. All of that is good; there is an inevitable price to be paid, and that is reflected not just in direct purchase and operating cost but also in the weight penalty and the effect that has on the rest of the 'system' - especially airframe robustness - that makes up an aircraft. However, those issues are not part of this debate.

 

Jabiru engines are without question, far less tolerant of 'out of condition' engine management and I presume (since I don't know, as I have zero interest in Rotax engines) also of proper maintenance. They are also far less tolerant of fuel quality issues. Despite the at times almost comically ignorant utterances of some self-proclaimed 'expert' commentators regarding some of the design/ manufacturing /metallurgical features of Jabiru engines, the 'scatter factor' between operational experience indicates pretty conclusively that engine management is a major factor in getting satisfactory life and reliability from Jabiru engines.

 

We have FTFs with histories of repeated early-life engine failures / incidents, and FTFs that report thousands of trouble-free hours on engines that came off the same production line. Since the engine is a common factor, one has to look at the 'uncommon' factors - operation and maintenance (and to a lesser degree, installation). There is a lot of ground to cover there and it isn't appropriate to the core discussion of this thread; suffice it to say here that there is quite enough evidence of disparity in the patterns of reliability experience between various operators to suggest that serious investigation needs to be undertaken to determine what significant differences there are in operation and maintenance and how that affects reliability.

 

That said, it remains a fact that Jabiru engines are at the 'fragile' end of the air-cooled aero engine spectrum and that they certainly have 'weak links' that can too easily be broken unless scrupulous attention is paid to their operation and maintenance - and yes, I agree that Rotax 912s are more tolerant, by a fair margin. CAMit improvements are designed to improve the reliability of the basic Jabiru engine design by addressing each 'weak link', based on research and development and testing. I agree entirely with those who say that Jabiru should achieve that same thing, and that Jabiru management are being obdurate in not so doing.

 

Once CAE engines have passed both of JAR 22H certification and ASTM certified testing, Jabiru could - if it wished and had the sense to so do - commence to deliver engines for LSA 24-reg, 24 'C' reg, and 95.55 reg Jabirus and bypass the CASA injunction completely. The necessary testing is an expensive business; to do the 'full 9-yards' of both standards, the cost is likely to be of the order of $500K or possibly more and take several months. However, both the necessary facility and the expertise exist. If CASA were willing to be co-operative rather than obstructive, the time and cost could be somewhat shaved; however the standards are explicit and must be met.

 

The hurdles to be jumped through for an engine manufacturer are extensive. It is worth noting that - as far as I am aware - the only certificated /certified engines that are realistic propositions for 'light sport' aircraft are the Rotax 912, the Continental 0200D, and the Jabirus. Neither Ul Power nor d-Motor are certificated / certified - at least according to their websites as of today. You could put them in your 19-reg Jabiru, or equally, put in a CAE engine and save a lot of money, but they are NOT candidates for 24 'C'-reg, 24 'D'-reg or 95.55 reg. Nor will they ever be in their current form under the existing standards, because they rely on EFI for achieving performance. So far, only Rotax has done the very, very extensive work required to get an EFI system that meets the standards. Rotax has a US$9B annual turnover company behind it - and as we know, the 912 iSc has not been without problems!

 

So - while there are potential solutions available to meet the 'problems' nominated by CASA as the reason for its action, it is in no way as simple as 'just do 'X', FFS, and all this would go away'. There is no silver bullet.

 

And the question still remains: is the CASA action appropriate to and justified by the unreviewed and withheld data it claims validates the action? Why are not certain aircraft that have known and documented structural / aerodynamic /occupant safety deficiencies that have and do kill people not been subject to the same sort of limitation? If it is OK to slap a limitation on one manufacturer on the basis of 'probability' - that has not resulted in a corresponding spate of statistics of that 'potential' being realised in 25 years of operation - why has CASA not also similarly acted where there are known and documented problems?

If as you sugest , the J engines are the same and the problems are difference in operational handling and maintance , wont by that logic , those same operators trash and break the camit engines as well???

 

Aircooled is aircooled ,

 

Go liquid cooled !

 

If weights an issue , i lost 17 kgs by just not having enough money to buy food . ( joke)

 

Realy , i just started to eat smaller meals !

 

Mike

 

 

[Yenn]

So noe we have someone saying that the operators who trashed Jab engines are now trashing Camit. Go to water cooled.

 

I would like to see data which proves this point.

 

I would also ask what happens to Franklin, Continental, Lycoming and Rotec amongst others. Aren't thay mostly air cooled and also reliable.

 

The failure rates for all these engines are not given for comparison, by those who have them, nor are the failure rates for Jabiru

 

 

[turboplanner]

Just someone making his own comments Yenn. Don't sit up late waiting for CASA to limit all GA aircraft.

 

 

[Oscar]

If as you sugest , the J engines are the same and the problems are difference in operational handling and maintance , wont by that logic , those same operators trash and break the camit engines as well???Aircooled is aircooled ,

Go liquid cooled !

 

If weights an issue , i lost 17 kgs by just not having enough money to buy food . ( joke)

 

Realy , i just started to eat smaller meals !

 

Mike

Mike: ANYTHING can be broken by someone... but yes, you are absolutely correct: the CAE engine is air-cooled and therefore it will still require attention to operating practices; it uses solid lifters so therefore will require more frequent checking of valve lash etc. (though operational experience is now starting to mount, that shows a very significant reduction in changes that are common on Jab engines [valve lash, head re-torquing etc.] which indicates that the CAE engines are handling 'real life' use with fewer effects.)

 

The water-cooled head option for Jab/ CAE engines (Rotec) cannot be certificated / certified because of the electric water pump, so its a dead-end for 24-'C' and 'D' reg. aircraft, unfortunately. I believe the 0200 D is about 91 kgs installed, dry weight, which is around 7 kgs heavier than the J3300 'ramp weight' and about 28 kgs heavier than the J2200 'ramp weight', for a hp of exactly mid-way between the two. I don't know just how much equivalence there is between claimed 'installed weight' and 'ramp weight' for the 0200D, but 'ramp weight' is a pretty reliable figure (I believe) to expect when it comes time for the W&B...

 

Getting back to 'operator' effects... Ian Bent is absolutely aware that he cannot build an engine that will withstand a lover-fingered user. However, he has concentrated his efforts on making the parts of the engine that are most likely to give up the ghost without a decent fight back against poor engine management, and much discussion has taken place and further research is being and will continue to be done, on ways to reduce the incidence of poor management.

 

Now, it MUST be stated that 'poor management' does NOT mean 'intentional poor management' - though I think most people know of instances where some owners / operators frankly should not be left in charge of a rubber duck in a bath let alone an aircraft engine. Prime causes of 'poor management' are firstly: a lack of full condition reporting (and recording, for preference, so that later analysis can be undertaken) due to inadequate instrumentation, and the quirks of cooling set-ups that do not provide reliable and even cooling in all circumstances. A close third cab off the rank would be fuel quality, with particular respect to paying attention to the performance of the fuel actually being received by the engine - not just the fuel that one thinks one put in the tank.

 

Jabiru does not provide a cumulated, clear set of 'user notes' for the guidance on the 'care and feeding' of their engines, it does not mandate (though it does recommend) what most sensible people would regard as adequate instrumentation, and its cooling installation is only just adequate for careful use in 'average' conditions.

 

To cut a long story short(ish): CAE are looking very hard at all of the 'management' and 'installation' issues and developing strategies to improve / assist in these areas as a parallel exercise to the engine developments. The full extent of that is yet to be decided, but it is reasonable to assume that the following will be either mandatory or at least very, very strongly recommended before CAE issues a 'full' warranty for its engines: full cht and egt instrumentation, with recording facility for analysis purposes and a revised cooling installation with audit of cooling performance a la Lycoming. I also expect there will be rather better and more useful user documentation supplied.

 

 

[motzartmerv]

So how many camit engines do we base all this " fix" data on?

 

How many camit engines are fitted to training aircraft?

 

 

[motzartmerv]

Roughly??

 

 

[Oscar]

Merv, those figures have been already supplied, and quite obviously none have been fitted to 'training' aircraft. You are just being needlessly tiresome, I expect.

 

 

[motzartmerv]

Ok. ( rich coming from you)

 

So refresh my memory ?

 

 

[AVOCET]

Now kidies !!!

 

Go eat some xmas cake , was your teeth

 

Go to bed , say your prayes , wake up tomorrow , and love one another .

 

You know , good will and all that .

 

 

[Oscar]

Ok. ( rich coming from you)So refresh my memory ?

See YOUR posts #234 and #238, this thread.

 

 

[facthunter]

That's about 300 posts ago. Nev

 

 

[motzartmerv]

MY posts?.. yes I see the answer was about 30?.. Not a huge data set. And NONE in school aircraft. Call me naive, but why are some placing so much stock in this engine? While in the same breath rubbishing an engine with over 50000 units world wide?

 

Its a genuine question Mr Llewellen, so spare me the valued judgments, and try and keep your response below the word count of your last two pages of offerings (1866 words in 2 posts..Some sort of record surely?) And Im tirseome ?

 

 

[jetjr]

Also see 2009 ATSB data. Be interested in pre 2009 data the same.

 

I think this might be pre hydraulic lifters, OK to be wrong if someone else knows when they were introduced

 

CAE starts it engine development from this point

 

Should have been some in early LSA Jabirus (not LSA catagory but certified models called "LSA")

 

There were issues with Solid lifter engines, hotter heads, lean burn kit and other things which have been addressed.

 

No one is rubbishing Rotax, they are a great engine, most anyone has said is they arent as perfect as many believe.

 

 

[Oscar]

Merv, I'm not going to be goaded into a complete waste of my time and this thread. End of.