CASA - Draft Proposal for Jabiru Aircraft

[facthunter]

Before you feel comfortable with those figures an aircooled aero engine doesn't put out a lot of HP per cubic inch. Never has.... 2,000 cubic inches gives about 1400 HP reliably when well designed. 50 hp per litre is about where it is... Nev

 

 

[bexrbetter]

Bex...You are on the ball .

Just want to make it clear this is stuff I know of, not about. The people in the area of NVH are very clever indeed.

 

but then second thought's it is actually abnormal cyl pressure that's causing ,

Sure, but that can go straight back to flexing the crank about causing TVs.

 

 

[Dafydd Llewellyn]

Question: How can the through-bolts be failing if they are not stressed above the fatigue limit? Surely the cylinder pressures can be measured? I can imagine a sensor hole, a lot smaller than a spark-plug hole, being put into a test engine and connected to a data-logger.Gosh I'll volunteer my engine if CASA can't afford one after all their executive salaries. Dafydd, you did once say that instrumentation was the hardest thing, but is it so hard?

Wow if there are no excessive pressures and the bolts then fail then I will apply for a refund of the

 

fees I paid doing my masters in mechanical engineering. I will sign up for astrology and stuff.

Multiply the pressure load by the leverage ratio of the "ears" of the cylinder flange; it's not a direct load path. The flexure of the flange also puts bending into the bolts.

 

 

[facthunter]

Trying to keep the engine compact.(not too wide) makes the conrod angularity very large. This gives big sideloads on the cylinders . Shear on the studs and load transfer to one side . Cyclicly.? Nev

 

 

[DWF]

I know very little about the finer points of torsional vibration and other loads on engines but it occurs to me that most testing is done while the engine is stationary in a test bed. Could the offending force(s) [assuming that is the problem] be generated or triggered when the aircraft is manoeuvering? In an incipient spin recovery exercise the aircraft [and hopefully the engine] is moving in 3 physical dimensions and the poor little pistons are reciprocating up and down (or backwards and forwards - as the case may be) and being subjected to all sorts of accellerations/decellerations and other forces. I dare say that at such times some of the bits in the engine have a hard time determining which way is UP.

 

 

 

Is this a valid scenario/question or have I lost the plot?

 

 

 

DWF

 

 

[Dafydd Llewellyn]

Trying to keep the engine compact.(not too wide) makes the conrod angularity very large. This gives big sideloads on the cylinders . Shear on the studs and load transfer to one side . Cyclicly.? Nev

All true - but probably not relevant. Basic reason for V engine.

 

 

[deadstick]

Righto...I'll drop an email to Darren Barnfield and see if I can get to the bottom of it thenAndy

Andy

 

It's all to do with the type certificate, The Jabiru UL-D and J160-C are Type Certified by the Civil Aviation Safety Authority (CASA).

 

The J120-C, J160-D, J170-D and J230-D are designed and built to ASTM Airworthiness standards.

 

Difference:-

 

A J160-c has a type cert whereas the latter D models have a special type cert. Both fit in as LSA' s but the engineering authority is different (CASA vs Jabiru) and both can be registered 24 if factory built.

 

 

[facthunter]

DWF when you consider these factors while they exist you have to consider the order of magnitude of them and they are often relatively of little consequence in what's really going on out there. Manoeuver, "G" loads are relatively small when added. Sometimes gyroscopic loads have been significance, particularly with propellers at high RPM, and high rates of turning.. Nev.

 

 

[bexrbetter]

Trying to keep the engine compact.(not too wide) makes the conrod angularity very large. This gives big sideloads on the cylinders . Shear on the studs and load transfer to one side . Cyclicly.? Nev

As Spock says; "Nothing that is impossible is possible" - certainly could be a part of the total sum.

 

 

[jetjr]

Accellerometer used for prop balancing should pick a tv spike up

 

I have one and it can be set up to read results alll the time.

 

We use he same thing to measure wear rates in large electric motor bearings

 

 

[turboplanner]

Seemingly went over Kaz's head too and Kaz is smarter than most and has the qualifications to match. What is your legal background Turbo? Are you a public liability legal specialist?What is the relevance of a licensed coxswain reversing over a diver after all divers weren't accounted for in relation to CASA's action against Jabiru?

The message got through to where I wanted thanks,and as I said before, but will do the two time thing for you, it had nothing to do with a coxswain, a boat, reversing, or a diver.

 

You might be better positioned confounding your buddies back on pprune.

 

 

[Guest Ornis]

It's easy for CASA and private pilots: "Fly at your own risk, CASA bows to your superior skill."

 

But what must CASA do for student pilots, in general? Jabiru seems to be arguing CASA must concede students must know how to deal with an engine failure, otherwise they wouldn't be allowed to go solo. Maybe the answer is in the numbers. How many hours before a solo cross-country? Ten? Twenty? Hundred? Thousand?

 

Maybe a plaque: "Fly at your own risk, CASA bows out."

 

 

[Admin]

In regards to TP's post, although very cryptic, I took it as you don't need to pull an actual trigger to be culpable which is very applicable in our industry not just specific to this thread. If you "knowingly" have bald tyres on your car and have an accident killing someone then it can be considered as pulling an actual trigger. Taking off in an aircraft that you knowingly has something wrong with it like a crack in the wing etc then you can be culpable if there is an accident and someone is injured.

 

That is the way I took the post but as I said, very cryptic and I am waiting on confirmation that this was the intent before any action is taken

 

 

[Admin]

In regards to TP's post, although very cryptic, I took it as you don't need to pull an actual trigger to be culpable which is very applicable in our industry not just specific to this thread. If you "knowingly" have bald tyres on your car and have an accident killing someone then it can be considered as pulling an actual trigger. Taking off in an aircraft that you knowingly has something wrong with it like a crack in the wing etc then you can be culpable if there is an accident and someone is injured.That is the way I took the post but as I said, very cryptic and I am waiting on confirmation that this was the intent before any action is taken

Intent confirmed but perhaps a bit too cryptic, so let's move on

 

 

[kaz3g]

In regards to TP's post, although very cryptic, I took it as you don't need to pull an actual trigger to be culpable which is very applicable in our industry not just specific to this thread. If you "knowingly" have bald tyres on your car and have an accident killing someone then it can be considered as pulling an actual trigger. Taking off in an aircraft that you knowingly has something wrong with it like a crack in the wing etc then you can be culpable if there is an accident and someone is injured.That is the way I took the post but as I said, very cryptic and I am waiting on confirmation that this was the intent before any action is taken

Yes, but the quoted example doesn't actually support that contention. The circumstances described in the Age article, if proven, relate to the allegedly negligent actions of the operator of a seaworthy vessel (in survey). The vessel is ok but the operator is allegedly culpably negligent in the operation of it.

 

This is not, in my view, the same as the situation a person might find themselves in if they lawfully operate an airworthy aircraft in a responsible manner and in accordance with the ANRs and the POH, but despite this, experience an engine failure.

 

In the case of an aircraft, especially a light aircraft, there is always the possibility of an engine failure that could have catastrophic results. Parliaments have already recognised this in their various iterations of the Wrongs Act.

 

The question that begs to be answered is at what level of known risk of engine failure can mens rea be imputed to the pilot, the manufacturer and the Regulator? The answer, at the moment, seems to be "it depends".

 

Kaz

 

 

[Dafydd Llewellyn]

Thanks, Kaz. This might be an appropriate point for a little history lesson:

 

In 1993, the Howard Government had, in its election platform, the introduction of an "American-style experimental category" into the Australian Civil Aviation Regulations; the SAAA and AOPA had been pushing for this, for decades.

 

The Howard Govt got into power in 1994; and in 1996 the then Minister, John Sharp, set up the Review of Regulations; and one of its marching orders was to make good that election promise. The American Experimental "category" exists because the U.S. constitution gives the individual the right to elect to take a risk, if he so chooses. Australians wanted that same right, in regard to recreational aircraft. The US experimental "category" appears in FAR Part 21, regulations 21.191 thru 21.195. (They are, nowadays, in the same place in CASR Part 21). However, Australia did not have a Part 21 in its regulations in 1996, because the people who wrote Australia's CARs did not dream that anybody here would be so silly as to to actually build an aeronautical product; the regulations were written about importing such products and maintaining them. (Oh, there were a couple of makers of wood propellers, but they were covered by ANO 108.28 and 108.29-which still exist, by the way).

 

The whole thrust of the CARs was paternalistic - protecting people from themselves, whether they wanted this or not. This was almost a religion within DCA/CAA/CASA; and the problem was (and still is) that the experimental provisions turn that completely upside down; they are based on voluntary acceptance of risk - just as is slowly becoming recognised for any "inherently dangerous" recreational activity, as is shown by the precedents set in NSW by Campbell Vs Rodney Victor Hay, and Echin vs STGC. So we have this little "bubble" of rebellion (or freedom, take your pick) buried inside a vast body of wholly paternalistic regulations that are fundamentally designed to protect Auntie Flo when she flies off to visit her grandchild. Some people have difficulty in grasping this temporary reversal of gravity as one passes across this little section of the CASRs.

 

So ANY aircraft that is essentially "experimental" in nature - however disguised by an E24 or a 19 registration, or by any other means, should have a prominent placard stating that it does not comply with normal aviation safety standards, and persons flying in it do so at their own risk. (I wanted the words "Abandon hope all ye who enter here", but I was overruled, and the message is toned down more that I think it should be, but a message is required to be there).

 

This also necessitated that CASA be given an immunity to negligence in regard of these aircraft, in the form of CASR Part 201.003.

 

The message has not yet fully seeped through to the courts (edited - Mod) - or, indeed to the drafters of the Jabiru engine Instrument, in that they included experimental aircraft. But it is quite clearly evident in CASA Advisory Circular 21.10; and anybody who is still having trouble with the whole idea should read that AC.

 

(edited - Mod)

 

Some manufacturers in the U.S.A. wanted to be able to sell what amounted to sub-standard aircraft as fully-manufactured products rather than as 51% rule kits; so they sought a half-way house - the first attempt was the Primary category; but the sole example with an FAA primary category TC was (and still is) the Australian Seabird Seeker. So they tried again, and the "consensus standard" put out by the ASTM was the result - and this made things a lot simpler for new entrants to this manufacture industry; but make no mistake, these are sub-standard products with a limited imprimatur, and limited application. They are only a whisker above experimental, and if you modify them without the manufacturer's consent, (or if the manufacturer ceases to exist) they revert to experimental.

 

 

[planesmaker]

Well said Dafydd

 

 

[motzartmerv]

Th RAA's official response to CASA.

 

Wowww.. Talk about taking a glove to the face of CASA.. A very clear message from the RAA, " YOU...ME...CARPARK...NOW"!!!!!

 

https://www.raa.asn.au/wp-content/uploads/2014/11/RA-Aus-Submission-to-CASA-re-Jabiru-Proposal-dated-21-Nov-2014.pdf

 

 

[fly_tornado]

More like RAA begging CASA pls check our pilot registry for hundreds of clerical errors...

 

 

[motzartmerv]

I like Monk, I like his style. But i wonder if this is the best approach. I hope it was considered properly, it seams a real " playing the man and not the ball" response. Fingers crossed CASA dont behave the way they have for the past 20 years when confronted.

 

 

[Keith Page]

More like RAA begging CASA pls check our pilot registry for hundreds of clerical errors...

Hello F_T

 

Your case ---- you will not be a bother as you are not a member.

 

However what do you fly these days? Waiting for an answer.

 

Regards

 

KP.

 

 

[fly_tornado]

Jabiru have stated many many times that the engine is perfectly reliable with proper maintenance, obviously the RAA technical certifications aren't worth the paper they are written on.

 

CASA needs to audit the registry and see if the L2 mechanics know how to maintain Jabiru engines correctly.

 

 

[terryc]

Well, it has been stated on this site in a number of threads that raa should stand up to casa. Now they have we all need to stand behind them. Some will bemoan the cost to them and the possible ramifications to their flying privileges, I say you can't have it both ways. I commend the president for what appears to be a very strongly worded letter, the intent being to solicit action, if the action is to be the one we want and need the casa needs to see a united front from all of us. Sit down hang on and enjoy the ride.

 

 

[DGL Fox]

There are pages and pages of what should be done from everyone on the site but I have not seen one official response from the other main party Jabiru...are they doing the head in the sand thing and hoping it will all just go away or maybe they a getting a measured response together and surprise us all with what they plan to do about all of this...

 

David

 

 

[fly_tornado]

Jabiru will do all they can to avoid releasing the data on their engine rebuild business, my guess is its the only part of their business that generates any profit.