Jabiru limitations

[motzartmerv]

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

Ok. No problems Oscar. Sure theres others that have an opinion on the matter. While I appreciate your opinion and point of view, im sure there are others around who have actually operated the engines we are all talking about, and I would value their input on why the CaMit engine seems to be the holy grail.

 

 

[JEM]

Good fireside reading for all. Go to the Pro Pilot site and read the article "Indecent Haste"

 

 

[fly_tornado]

so no announcement from Jabiru yet?

 

 

[Oscar]

Ok. No problems Oscar. Sure theres others that have an opinion on the matter. While I appreciate your opinion and point of view, im sure there are others around who have actually operated the engines we are all talking about, and I would value their input on why the CaMit engine seems to be the holy grail.

Fine. I suggest a good start would be reading through the entire 'CAMit engines - anybody got one?' thread.

 

 

[gandalph]

.......While in the same breath rubbishing an engine with over 50000 units world wide?I

Oscar said just a page or so back: "

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;

 

Hmmmm..... Seriously rubbishing the opposition with that comment. Like being savaged by a gummy sheep. I imagine Rotax will be seeking a restraining order after that condemnation.

 

Snickers time again?

 

 

[Gnarly Gnu]

Good fireside reading for all. Go to the Pro Pilot site and read the article "Indecent Haste"

Do you have a link JEM? The only possible site I could find was down.

 

 

[Oscar]

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

The 2200C introduced hydraulic lifters for certificated engines, TCDS issued 6 April 2008: you can Google it, copying link seems to have some issues.

 

 

[motzartmerv]

Oscar said just a page or so back: "

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;

 

Hmmmm..... Seriously rubbishing the opposition with that comment. Like being savaged by a gummy sheep. I imagine Rotax will be seeking a restraining order after that condemnation.

 

Snickers time again?

Oh gandy... The thread coppa..

 

That's a nice para you dug up. Good job.

 

You two want a room?

 

 

[skeptic36]

Good fireside reading for all. Go to the Pro Pilot site and read the article "Indecent Haste"

Any chance you could put up a link for that

 

 

[gandalph]

Oh gandy... The thread coppa..That's a nice para you dug up. Good job.

You two want a room?

:spot on:Well I just thought you might've missed it amongst all the other words.....

 

NO I don't want a room, I'll leave you two lovers to kiss & make up.

 

You sure you two aren't siblings? You sure sound like you are.

 

Maybe father and son????

 

 

[Oscar]

Oscar said just a page or so back: "

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;

 

Hmmmm..... Seriously rubbishing the opposition with that comment. Like being savaged by a gummy sheep. I imagine Rotax will be seeking a restraining order after that condemnation.

 

Snickers time again?

Forget it, Gandalph. This is another pretty crude attempt to drag the thread back to tribal fighting when the rest of us were making some progress.

 

 

[motzartmerv]

Or, an attempt to get Info.. But you keep pushing your little wagon sweety.

 

 

[Guest Ornis]

I have been asked what engine I would recommend to replace a Jabiru. I can only offer my thoughts after my 3300 broke a valve ~1200 hours (top end overhaul ~800 hours) and I was lucky enough to land deadstick without damaging the aircraft. My wife advised buying a new aircraft, bearing in mind the huge amount of time I spent fiddling with it and the trouble I'd had dealing with Jabiru. I might have looked at several aircraft, all Rotax-powered, but actually the J200 suits me. I can put two Giant Half-Way fold-up bikes and camping gear in the back.

 

Initially it was my intention to rebuild the engine using reconditioned heads I had. The crankshaft looked fine although all six pistons had compressed lumps of broken piston into the heads. I needed a new barrel and conrod (I had sourced pistons from ACL in Auckland before and had the ring-clip groove machined).

 

Ian Bent explained why I should not re-install the old crank: its life had been shortened by an indeterminate amount. We spoke for some time. He remembered meeting my wife and me some years ago. I like and trust him.

 

When I looked at the numbers (yes, yes, numbers, the dollar in the pocket doesn't leave much to the imagination) I decided it made good sense to rebuild the engine to CAMit specifications. Normally this is done by CAMit but Ian agreed to ship a core. I fitted the steel "star" that meant there was now no aluminium in the flywheel-gearwheel-crankshaft stack, but torqued the capscrews to nearly 50 N-m. I declined the belt-driven alternator as frankly I don't think the existing alternator is the problem with the joint.

 

After 12 years nursing and cursing a Jabiru I believe I now know enough to get a good run from a new engine. Thanks, Jabiru, all learning is good but your "course" is expensive. I believe CAMit has made several improvements and Jabiru has gone off on a tangent.

 

I did consider ULPower as I like the fuel injection and inlet port at the top, but it is expensive with no clear benefit.

 

I didn't seriously consider Rotax as I don't especially like the 912S and it's a very expensive exercise. The 914 is outrageously expensive.

 

So, my advice would be to fit a CAE or rebuild your Jabiru to CAMit specifications. I would take great care with the installation and engine monitoring, it remains an engine susceptible to overheating. Regular maintenance will disclose this but it's to be avoided. I would be talking to Oscar, jetjr and others with particular experience. Ian Bent will set you on the right track.

 

 

[gandalph]

Or, an attempt to get Info.. But you keep pushing your little wagon sweety.

Sweety!? Aw shucks! And all this time I thought you didn't like me.......

 

 

[JEM]

Sorry all. My bad.

 

The website is Pro Aviation.

 

proaviation.com.au/

 

 

[JEM]

This is the article. Pro Aviation website

 

Pro Aviation

 

Sharp End Aviation News and Features

 

Indecent haste

 

Jabiru Aircraft’s Managing Director Rod Stiff has written to Infrastructure Minister Warren Truss in outrage over what he describes as “an unprovoked, unjustified attack on Jabiru and Light Sport Aviation.”

 

Jabiru markets a range of eight light sport aircraft models – four factory-built and four kit-build units. The company has sold 1547 aircraft into 47 countries, and has sales representation in over 70 nations. Jabiru also manufactures and markets four and six-cylinder engines either as finished units or “firewall-forward” conversion kits to replace other engine types. The company also produces power plants for at least one the world’s biggest manufacturers of unmanned aerial vehicle (UAV) “drone” aircraft, which demand high reliability because of the value of their high-technology payloads. Jabiru has sold about 250 engines to that manufacturer over the last 15 years and at peak production, produces 20 airframes and 50 engines per month.

 

 

“The action was taken without enquiry, without facts, and by way of a published statement that harms Jabiru, and was immediately published internationally,” says Mr Stiff. (This narrative is directly drawn from information supplied by Jabiru and RA-Aus.)

 

CASA launched its action on 27 October 2014, with a request to RA-Aus for specific data relating to operations of Jabiru aircraft and a specific deadline of November 10, requiring significant investment of RA-Aus resources. The information requested was for the stated purposes of a proposed SASAO (Sports Aviation Self Administering Organisations) audit of Jabiru’s operations on 17 November 2014. The data provided contained information on incidents and accidents involving Jabiru engines for the year to date, covering the period from 1 January 2014 until 27 October 2014.

 

RA-Aus formally submitted the information to SASAO on 3 November 2014.

 

On 4 November 2014 CASA engaged directly with Jabiru in relation to the proposed restrictions on Jabiru aircraft which included all aircraft manufactured by Jabiru as well as those non-Jabiru aircraft that have a Jabiru power plant. In this notice CASA clearly states: “Prior to making the instrument, CASA invites Jabiru to make representations about the terms of the proposed instrument…”

 

In the days immediately following, Jabiru arranged to meet with CASA on 14 November 2014 to address the concerns and to take advantage of the opportunity to discuss the terms of the instrument as outlined in the regulator’s notice. This meeting was also intended to action CASA’s request for Jabiru to respond by 10 November although it should be noted that due to illness of key CASA staff the meeting could not take place by the required date and that CASA agreed to extend the time. At this point Jabiru was led to believe that the proposed instrument would not be published until after the scheduled meeting.

 

On the afternoon of 13 November CASA pre-empted the outcome of the scheduled meeting with Jabiru and effectively ended the consultation with the manufacturer by publishing the commercially destructive ‘proposed instrument.’ This occurred some 18 hours prior to the scheduled consultation with Jabiru.

 

The derogatory information circulated by CASA said:

 

CASA is responding to a high, and increasing, rate of engine failures among aircraft that are powered by engines manufactured by, or under licence from, Jabiru Aircraft Pty Ltd (Jabiru). Such aircraft are referred to in this document as ‘Jabiru powered aircraft’.

 

The issues appear to be the result of several failure modes, which require separate investigation.

 

CASA has formed the view that its functions under the Civil Aviation Act 198 8 require it to mitigate certain risks to passengers, trainee pilots and persons on the ground.

 

The instrument will impose operating limitations on Jabiru powered aircraft that are issued with a CASR Part 21 authorisation by way of conditions under CASR 11.068.

 

CASA went on to list a set of proposed operating limitations on Jabiru-powered aircraft, including limiting them to day VFR operations only, not overflying populous areas, forbidding carraige of passengers, banning solo flights by student pilots, and displaying warning notices that “occupants fly in the aircraft at their own risk.”

 

RA-Aus says that even in the days prior to this the organisation began receiving enquiries from concerned members noting that CASA officials had made mention of the proposed actions ‘over a beer or two’ during the national Chief Flying Instructor conference held by RA-Aus. The conference is an annual event designed to inform RA-Aus instructors on new developments, changes to rules and generally improve safety in the aviation industry through the provision of training and education. It is fully funded by RA-Aus with no support from CASA or any other public source of funds

 

Following the publication of the draft instrument RA-Aus was “inundated” with communication from aircraft owners, flight training facilities and aircraft maintainers expressing concerns about the proposed restrictions and the potential impacts on business viability and reputational damage as a result. It should be noted that the information provided covered a period of less than one year and should have resulted in deeper engineering analysis by CASA as to root causal factors, along with requests for further detail prior to any action taken by the regulator. RA-Aus says it is firmly of the view that any conclusions drawn from the data are deficient in detail and do not address fundamental issues relating to potential manufacturing, operational and any other possible deficiencies:

 

“At the time of writing [the submission to Warren Truss] it has become apparent that CASA recognised this deficiency in terms of their understanding of the data that was provided on 3 November. On 18 November CASA wrote to RA-Aus seeking instruction on how to identify 28 engine related issues referred to earlier in this submission. It is of serious concern that CASA does not only provide a basis for its decision, it does not understand the data provided by RA-Aus and has acted on a flawed understanding of the issues.”.

 

“Jabiru rejects outright the suggestions implied in this threat which was made without warning,” Mr Stiff has told Minister Truss. “The public international threat to the company with its damaging effect on Australian aviation and safety should be immediately ended through withdrawal by CASA,” says Mr Stiff.

 

Michael Monck, President of the RAA, has already sent a separate document to CASA which Mr Stiff describes as “very forthright.” (See previous article, Get on with it!)

 

The most serious aspect of the entire CASA action was the distortion CASA applied to the raw information from RA-Aus, says Mr Stiff: “We vetted the whole RA-Aus list when we finally got hold of it. CASA actually asked RA-Aus for their numbers after they had drafted the instrument – they didn’t have anything until I asked RA-Aus and they sent them their unedited list of incidents which included everything and listed 40 engine failures, so that’s where CASA’s magic 40 figure came from.

 

“Jabiru had addressed most of the identified problems over three years ago. I believe CASA has been negligent because they never consulted with us before they introduced the consultation draft, and they pulled the rug out from under us while we were on the plane on the way down. They couldn’t wait another day to talk about the issue, which really tells you what the intent was; the intent was obviously to damage us to the point where we couldn’t survive.

 

“When we finally worked that out with RA-Aus we spent a whole weekend going through the 40 events, comparing it with our list of failures, and working out which were just maintenance items like leaking fuel pumps, or simply running out of fuel, which were all on the CASA list. When we’d tidied it up we actually added some to the CASA list and when that was sorted out there were 12 actual in-flight engine failures which led to genuine forced landings. But that was in 93,000 flights, and 43,000 flying hours. And it was mainly flying schools because Jabirus are such popular training aircraft. We already had corrective measures in place for almost all of those 12, and had implemented them since 2011.”

 

In earlier discussions, Jabiru had offered CASA information from a detailed survey of light sport aircraft safety in the United States, conducted by Aviation Consumer magazine, which placed Jabiru’s safety record in the top three of over a dozen types along with Cessna 152 and Cessna Skycatcher in three categories:

 

• Overall accident rate per 100,000 hours of flight (Jabiru was second only to Cessna 152);

 

• Fatal accident rate (Jabiru’s score was zero in USA); and

 

• Accidents per hundred aeroplanes registered (Jabiru was second only to Cessna 152 and Skycatcher.

 

“Of a claimed 40 Jabiru ‘engine failures’, the actual number of genuine failures is only 12 out of over 1500 aircraft. And there has not been a single fatality, and very few injuries.”

 

“Jabiru has settled CASAs concerns. We are looking forward to Mr. Higgins from CASA coming to Bundaberg as he has said, to see these outcomes. For example, Jabiru has not had a recorded through-bolt failure in any engine produced since 2011.

 

“The evidence available to Jabiru shows there have been no deaths in Jabiru aircraft arising from engine stoppage. That is the case internationally. Between January 2013 and November 2014 there have been a number of deaths in light sport aircraft in Australia in other aircraft than Jabiru. CASA ought to be addressing that matter.

 

“CASA should also be looking elsewhere for more serious air safety issues in light sport aviation. If 19 deaths did occur and none was in Jabiru aircraft, then CASA ought to be attending to those issues, and not attacking this company without notice.

 

“Turning to the substance of the response demanded by the CASA, the issues of Jabiru engine operation to which it relates have effectively been resolved. There was no need for the world-wide denigration of Jabiru.”

 

 

[Guest Ornis]

There was a court officer called gandalph

 

Who heaped great love 'pon his self

 

He saw his forte as rationality

 

Pooh-poohing others' banality

 

But actually he's a pain in the ... good health!

 

 

[motzartmerv]

Sweety!? Aw shucks! And all this time I thought you didn't like me.......

Wasn't for you...but there's plenty of love to go around:))

 

 

[Oscar]

Ornis - the belt-drive alternator doesn't have a primary effect on the flywheel attachment per se, but it does provide some harmonic balancing to the crank which somewhat reduces the oscillating forces on the flywheel, so you might consider it as a 'secondary effect' improvement. (As an additional 'value-added' for the CAMit alternator, the use of a standard automotive-type regulator will give you a far more reliable voltage delivery, which you'd appreciate if you run an iPad/iPhone off a cabin-power outlet or want to run a LiFePo4 battery - neither of which I'd be keen to consider with the standard Jab alternator set-up.)

 

I wouldn't be too eager to pull the capscrews to 'shit-all' tight, as there isn't a huge amount of metal round the threads in the crank and if you raise the end of the threads you'll actually reduce the friction grip between the flywheel and the crank. I don't have the CAMit assembly manual for CAE engines here with me at the moment to check (it's a more useful document than the Jab Manual) so I can't check what CAMit uses for cap-screw tension. It's a gamer person than I who'd try to second-guess Ian, he's done an awful lot of work on those engines..

 

Was your core assembled or was it just the components? If it was assembled then you probably haven't seen the new CAMit through bolts in the flesh, as it were, which is a pity - they are far more reassuring than the Jab ones.

 

 

[Guest Ornis]

Oscar, did >500 hours with ARP bolts torqued to 50 N-m (grease) after replacing the aluminium vacuum-drive with a steel spacer and installing a thick steel spreader under the heads. No dowels. No sign of a problem with the threads or the aluminium flywheel.

 

Ian knows more than I do but I still think the problem has always been lack of friction in the joint. Maybe Ian doesn't want to change without testing...

 

 

[Oscar]

Ah, my bad reading! I'm stuck in the groove of Imperial (for torque) - force of old habits. I saw 50 and snapped into 50-ft/lbs. I agree, 50 NM shouldn't raise a sweat on the threads.

 

 

[Guest Ornis]

50 N-m is ~37 ft-lb; the current CAMit/Jabiru torque value is 24 ft-lb (from memory) - which I "feel" is too low.

 

 

[Oscar]

That's what I think I remember from doing our engine at CAMit - 24 ft/lbs. But, we were doing the complete assembly in somewhat of a hurry so I certainly wouldn't put 2-bob on that being authoritative...

 

 

[Guest Ornis]

My response to Mr Stiff's indignation is: "Rod, you are going to bankrupt your company. You were in trouble before CASA stepped on your toes. You can jump up and down as much as you like but you aren't going to get your own way this time. Everything comes to an end and your number's up. Talking about numbers, ring Ian Bent - and be nice to him."

 

 

[Oscar]

Trying to get Rod to see anybody else's POV is like trying to get a fish to ride a bicycle... but that doesn't excuse CASA for playing a dirty game. Part of this saga has to do with internal CASA politics and to use Jab. owners and operators as cannon-fodder is an inexcusable abuse of power. The extension of the limitation to experimental aircraft is a clear contravention of CASA's own regulations; neither side is going to come out oif this looking at all good, and in the meantime, the collateral damage is already bad and could get far worse.