CASA - Draft Proposal for Jabiru Aircraft

[Teckair]

Quiet?Give me noise every time...

Yeah that's what the fuss is about, sometimes a bit too quiet.

 

 

[jetjr]

Yes it is way cheaper and I and many others dont care about 80 hp, I need 120hp to get mine off the ground as do much of the Jabiru fleet.

 

It more than an engine debate too. Really comes down to what you do with your aircraft and where youre based too.

 

Jabiru J200 $80 K, Anything with rotax capable of 120kts is rare and $110K plus and no where near as robust.

 

Theres $3K /year in interest straight away. I can replace my whole engine every 4 years (say 200hrs) and still be ahead.

 

Even a 914 alone is close to $20K dearer than 3300 and doesnt share 912 reputation. Very few can afford that.

 

My experience has not seen extensive ongoing costs, look after myself with solid supervision. Not much wrong in 900hrs.

 

Had I a 914 I would have been L2 servicing which would involve a long flight every time. few $000's every year at least

 

I have no fear for my loved ones, they regularly fly with me. If it stops I will land it, as trained and practiced and it will be OK. Less fatals in Jabirus than anything else.

 

ATSB data says even accidents occur at similar rates so the whole engine failure debate is a bit flawed.

 

Not being able to alter from a schedule when theres strong evidence to back it is the LSA problem.

 

Theres no doubt they need further development and problem is LSA owners need Jabiru to agree to changes, they may never do this.

 

Some maintainers should obviously stick to Rotax, shame they dont really.

 

 

[Geoff13]

Now I am confused. 80hp will get a J170 off the ground and flying at MTOW of 600kgs.

 

But you are telling me that most of the Jabiru fleet need 120hp. Since when did the MTOW on Jabiru's go up.

 

I would have thought that if 80 hp can get a J170 off the ground at 600kgs, then it would get just about anything up that runs to the same MTOW.

 

But hey I have been mistaken before.

 

But there you go again blaming the maintainers with no real evidence.

 

You say on one hand that if you had a Rotax you would need a long flight just to get it maintained but the Jabiru by your own admission you don't.

 

So which one is harder to maintain the one you do yourself in the back yard or the one you need to travel long distances to have done.

 

There seems to be a slight flaw in the logic here somewhere.

 

If I get time tomorrow I will do the maths on a 6cyl Jab compared to the 100HP Rotax. I hadn't considered them as they were not what I was looking at when getting prices.

 

Cheers geoff13

 

 

[Guest Ornis]

I have no fear for my loved ones, they regularly fly with me. If it stops I will land it, as trained and practiced and it will be OK.

Famous last words.

 

 

[Teckair]

Famous last words.

I have survived more than 20 forced landings, it is nice when it works but there are no guarentees.

 

 

[jetjr]

Yes your right i will lock them inside, turn on TV and close the curtains until they reach adulthood, everyone will be safe then - somewhat mentally damaged, but safe.

 

Of course theres risk, but "fearing for loved ones" bit dramatic?

 

If you think it wont be OK when something goes wrong, might be best to choose a less risky hobby.

 

Report says as far as accidents goes there isnt much difference anyway.

 

Whats not to follow, Jabiru are simpler to maintain, simpler overall. Ill bet more Jabiru's are self maintained, probably poorly maintained too, maybe theres more problems as a result.

 

Im not blaming anyone, it seems the regular excuse that it shouldnt have had issues because I have a L2 or LAME doing work on it, following the books etc etc. If they dont have the experience or ability to sort out and keep engine going theres a problem with the maintenance system. Could be their skills, currency, training, plenty of things not their fault. That includes the information in the manuals, parts quality, operation and setup

 

Ill take myself over a LAME with several failures to his name to do my work.

 

The maintenance SYSTEM for Rotax is very different to Jabiru. More developed product and service processes for a start. Also costs to match this.

 

Stating if the same guys runs one OK and the other not, its the engines fault, doesnt make sense.

 

I dont know or understand Rotax engines and wouldnt work on them myself with confidence. This would greatly increase service and repair costs. Its a valid reason to buy a Jabiru engined aircraft.

 

This always turns into how great an engine the 912 is debate, no doubt it is but it isnt available in an aircraft suiting many's needs, performance and price range.

 

Yes you should research how an up to 750kg 4 seat Jabiru will go with 100hp. Wont do much very well Id say.

 

Then some runway distances required by 80hp vs 120hp, around double.

 

Adjust this for DA you ll be towards 1000 m needed in plenty of places. Going to need more than IFA prop on a hot day and short strip. Also 20% slower.

 

If thats what extra $10k buys you it isnt going to sell very well and an extra $20K still is barely going to deliver the goods.

 

All a quite irrelevant because if you want a Jab aircraft and its features, you dont have a choice.

 

Getting back to the losers in this CASA proposal, its likely to be existing LSA owners and FTF.

 

A large section will be forced transfer to 19, or E, rego and get be allowed to have someone to sort out their engine problems without the restrictions of Jabiru and LSA.

 

They arent going to choose to swap out for a 912 as it still wont allow it to be used for training. might allow a single PAX though but so will CAE and thats a cheaper and simpler change.

 

 

[alf jessup]

Jetjr,

 

You are correct my friend there is a risk in flying no doubt but a far less risk than driving on the roads these days so I wouldn't be too worried about taking your family in it, your aircraft has a proven very well designed safety cell far better than anything on the market without question.

 

You have had a great run it seems as do others with your Jabiru and others have not and you have a right to defend your aircraft, others just haven't been so lucky and been stiffed so to speak, there just isn't enough consistency in them at the moment.

 

But the engine as you seem to agree is not a robust as the Rotax which is a fair call.

 

Once if ever these issues eventually get sorted Jabiru will then be the best value LSA on the market no doubt, but until the factory decide to get their head out of the sand and allow Ian Bent or others make reasonable improvement to them it is just going to keep going around in circles I think.

 

Cheers

 

Alf

 

 

[Old Koreelah]

Thanks for the pix and info, but I'm mystified by the second pic.

 

What is that big item protruding thru the back of the ram air duct?

 

There has been much discussion about how important it is for the duct to fit close to the engine. This one sure doesn't.

 

 

[Old Koreelah]

It's a fibreglass block, perhaps 1Inch x 1 inch by 1/4 inch, glassed onto the inside of the ram air duct.

It has a definite effect on cooling. Seems the more hot air you release, the cooler the cylinders all run. I was told you should be able to put a finger up the gap, so I tried something much bigger and it worked surprisingly well.

 

Ideally I'd relieve the entire rear section on the inner and outer end of the cylinder, however I haven't got that done yet, I didn't want to wreck my ducts.

Thanks for the reply, but I meant the dark-looking pipe sticking straight out thru the duct.

 

The fibreglass spacer you mention seems to be allowing mobs of cooling air to escape out the back rather than being forced down past the fins. Surely not a good idea.

 

 

[planesmaker]

Thanks for sharing that Deb. Tom

 

 

[Guest Ornis]

The problem is that when you close up the gap, it reduces the total amount of air that flows through the entire duct and thus affects all cylinders. The fins at that part of the head are their closest to the core of the head so as long as it's passing through the fins on the upper half you are all good. The lower half of the head shown in the pic is never going to get airflow without an entirely different cooling configuration.The numbers tell the complete story and a series of about 25-30 initial short test flights proved the theory for all of these mods. These mods have since been implemented on a number of other aircraft successfully.

Well, your theory and findings are the antitheses of what I would expect.

 

Where are you measuring the CHTs? Thermocouples? Where is the cold junction?

 

You're not just blasting air past the sensors/lugs, are you, and cooling them? (We use temperature sensitive resistors buried in a hole between the inlet and exhaust ports.)

 

There is a problem cooling the underside of the heads; insufficient metal/area/fins. Some kind of "spreader" would be helpful. Some earlier heads had three holes from the top down into the concavity between the ports. Personally I think that was a good idea but it's been dropped. Which probably means it was a good idea, but Jabiru didn't know that spreaders were needed spreaders to direct the air and hold it against the head.

 

In general terms, the lower cowl should have as lower pressure as possible. This means 1. An exit duct on the oil cooler. 2. As little air as possible passing down from the ramairducts without blasting the fins. That is my understanding. Your claim has thrown a cat amongst the "pigeons".

 

 

[jetjr]

Not really, the basics are what some owners have been saying all along. Only difference is opening rear up, pretty simple to test.

 

Pretty sure the Cae engine has deflectors/spreaders underneath.

 

This is what im talking about, Deb has worked to get cooling sorted out BEYOND what was done at factory OR what it says in the manuals, not contrary to them though.. These changes would be ok under LSA and Jabiru would approve if asked.

 

Some just say it didnt come like that so shouldnt be needed, for 10 years or so owners have been doing this type of work and getting better run from them. Its not a kit or one solution for all unfortuntely

 

The sensor problems all apply to factory instals too, so an owner seing 180 regularly could be much higher too.

 

CAE sell shielded cht probes

 

 

[jetjr]

Im on the same mission but bit different track

 

Fitted small deflectors over each cylinder, and gull wings underneath

 

I have extended cowl lip underneath

 

The small air deflectors had instant diference and ar tuneable by removing or adding material

 

This combo after lots of adjustments sees temps down between 100-120, occassionally below 100, still have issue that RHS is 20 cooler, trying to warm it up a bit

 

Will try the open back idea on LHS

 

My thermocouples are dynon std, crimped in brass and inserted down hole in head, going to fit rubber insulator to each

 

Im not chasing exact number so reading errors arent major concern. As said other signs of heating are gone, havent had headbolt or tappets need adjust for 200 hrs.

 

 

[01rmb]

Yea thanx for the advice.I'm glad your engine hasn't let you down in 400 hours, but your hardly in a position to be offerin advice on how to be a "reliable" operator after 400 hours mate. No offense but your a pup in this dog pit mate.

We have roughly the Same hours operating rotax aswel, so you really think I should ask what my lames are doing wron when we hve had no major iasues with them?

 

400 hours...lol.. I'm still laughing mate.

 

Come in here bragging about your awesome maintenance and operating.

 

Mate some schools do 400 hours in 3 months.

Merv - I have obviously really upset you - apologies - some of my comments have been pointed and were not useful - I really have no desire to offend you.

 

The comments I make here are based on the advice I have been given from my LAME who looks after a flight school was doing 300 hours per month on their Jabirus including my own aircraft. They have had their fair share of issues with the engines but have worked on ways to avoid these problems from reoccurring which I have passed on here in the hope to help others. There has been some helpful advice from Jabiru and some less than useful (including potentially poor maintenance from them (Jabiru) that actually caused a forced landing). Jabiru have a lot of things they can do better and working with customers who have problems is certainly one of them.

 

I do not profess to be anything other than a new aviator wanting to learn how to fly better and avoid problems. I am a pup in this game but have no less right than anyone else to share an opinion here. I listen, I learn and I pass on what I can in the hope that someone else may benefit from that.

 

 

[motzartmerv]

No probs.

 

 

[facthunter]

When the Rotax 912 came out it set new standards of reliability. It was hailed as the MOST reliable piston engine in aviation. ANY engine you compare with it will perform worse in reliability. That was the 80HP version.

 

Later models are not as reliable, it appears, so do we ban them or wait till they are as reliable (which may never happen). Do we require ALL engines to meet the Rotax 912 level of reliability?

 

Lets look at the proposition of fitting a CS (uncertified ) prop. Immediately you have probably sent the reliability to a new low and introduced a mode of failure that is potentially worse than just a power loss.

 

There is no prop safer than a two bladed wooden one.

 

Most of the Jab failures don't result in an engine fire. Many engine failures with other types can often run a big risk of engine fires. as they are not contained (oil leaks etc)

 

Ancillaries like coolant runs and oil lines and drives cause a loss of reliability to otherwise good engines. The smaller Continental and Lycoming engines operate without the need for an oil cooler. That is a point of reliability.

 

I doubt the Larger Radials had any better reliability than the Jabiru's. There were examples of multiple engine failures on one flight plenty of times, and the flights were not longer than 12 hours generally. and thing s were near new and maintained by world class airlines then. Nev

 

 

[turboplanner]

When the Rotax 912 came out it set new standards of reliability. It was hailed as the MOST reliable piston engine in aviation. ANY engine you compare with it will perform worse in reliability. That was the 80HP version.Later models are not as reliable, it appears, so do we ban them or wait till they are as reliable (which may never happen).

Quite a few people have tried to turn this thread into a competition between engines, or espoused their completely reliable experience in 400 hours as an example that every other aircraft with that engine will be the same.

 

However, CASA's action is based on CASA's statistics, not ours

 

 

[facthunter]

My point from the beginning has been IF you use this argument against Jabiru do you go after all the other engines that are not as good as Rotax 912?. Nev

 

 

[motzartmerv]

Merv - I have obviously really upset you.

Nah, im pretty thick skinned. I do react a little when people point to operation and maintenance. Not so much because I think we are perfect, by any means, but because we have always offered to take advice on how "better" to operate, or maintain.

 

My engineers have for the last few years, gone above and beyond what I would call reasonable measures to ensure compliance with the published procedures etc.

 

We operate them STRICTLY IAW with the POH. I mean to the LETTER!!!

 

Our failure rates, are exactly in line with what could be predicted from the stats with Jab engines. As ive said, we have more than 5000 hours over the years operating Jab engines, and have had one inflight failure, and several "ground" failures, ie, discovered in pre flights etc.

 

Those numbers align almost perfectly with what could be expected after operating for the hours we have.

 

Certainly not making excuses. If we knew HOW to improve things, we would.

 

* We can only operate IAW published specs

 

* We can only maintain IAW with published procedures

 

* We can only monitor with approved and installed equipment

 

Outside of that, what else can we do? We have provided as much data as we can regarding engine component failures.

 

We have NEVER had a satisfactory indications to WHY ANY of these failures have taken place. Apart from once when the factory admitted to supplying the WRONG part.

 

We have even had to FIGHT with Jab to get our "broken" components back off them for independent inspection. The line being, they cant explain it, and we cant have the parts back either..

 

We have had many 400 hour runs with ZERO reportable defects or failures over the years, so im sure you can understand my synasism when i read people's stories of perfect service over such a small period, and that being offered as "evidence" of our operational shortcomings with regards to failures. And when called an "idiot" and a "clown" I do get a little...Tired...

 

You are perfectly correct, your opinion is as valid as anybody elses. I appolagise if you took from my comments that you shouldnt be posting your opinion. But please understand that some operators have a greater "pool" of data on which to base their opinion.

 

 

[motzartmerv]

You gunna offer something one day Karoona?

 

 

[motzartmerv]

Yea. I thought as much. 7 years, zero offerings, but I bet many complaints and reports, and countless digs through your little icons.

 

Thanks for your input mate. The little 'YELLOW" icons are well suited to some.

 

 

[turboplanner]

My point from the beginning has been IF you use this argument against Jabiru do you go after all the other engines that are not as good as Rotax 912?. Nev

FH, reading what you have said over and over again, I'm certain you have not looked at the RAA statistics because they make the magnitude of the differences very clear.

 

If you see one risk, it can be a random risk.

 

If you see a cluster of similar risks, and you don't want to lose the farm or be prosecuted, the safest cation is to remove the risk immediately.

 

So in answer to your question, you go after all the engines which have a cluster of similar risks.

 

Where a known fault was occurring, such as bearing failure at 250 hours, you can schedule in bearing replacements every 250 hours.

 

Where there is a random issue which can strike some engines at 2 hours, others at 400 hours, others at 1100 hours and most not at all, it's like measuring a jelly.

 

However the one that counts is the one which goes down and injures or kills someone, then everyone looks back into history as to what action should have been taken and what action was taken........and the evidence is there on the ground.

 

 

[01rmb]

Thanks Merv - I do feel for people and especially flight schools that have had problems both from a safety consequences and cost. The flight school I am associated with had 6 Jabirus in use at one stage and 2 of those were doing over 30 hours per week each - so plenty of experience but also not without incident and challenges for the LAME.

 

I dread every time there is an aircraft problem of any nature but because I have one I am particularly concerned about Jabiru issues when they occur. I agree that Jabiru should do more to find out why there are problems and ways that problems might be reduced - just good quality and safety improvement practices. But unfortunately and sometimes in spite of Jabiru, our LAME recommended some maintenance changes to ensure better reliability and for us the biggest was around the fuel used. They also looked closely at indicators during preflight and the 25hr services such as how smooth the engine is running and any compression changes that might indicate a head needs to come off to check valves or rings. Indeed, a lot of what Jabiru has now come out with in the increased inspection recommendations was being done.

 

Again - apologies to you in that some of my comments were more directed at others with no experience of the problems or indeed impacted by the CASA response and were happier to sling poo at the guys doing 50-100 hours a year, just trying to enjoy themselves and trying to avoid unwanted attention from CASA.

 

 

[motzartmerv]

Did you guys go back to Avgas? Did this improve things?

 

All our pilots have become experts at pre flights, which is a good thing. Almost ALL of our failures have been picked up during pre flights. In fact, the fly wheel bolts on our 170 were found to be sheared when my instructor heard a very very faint clicking noise when she pulled the prop through. I was very pleased that she picked this up, I couldn't hear it...(im on the other side of a fair few AC/DC concerts) .It was an ever so quiet click as the ring gear contacted a surface it normally wouldn't due to slop in the fly wheel.

 

The pre flight is the LAST line of defence, and luckily for us, has almost always identified the issues before they cause more damage or worse.

 

 

[facthunter]

It's pretty obvious that operating a motor that tends to run hot with Mogas of often dubious quality is likely to cause problems. Remember the Jabiru recommended Avgas, but that has it's own problems with deposits. The fuel problem (quality)as well as the deposits are likely to result in detonation which can cause horrific damage. particularly in two strokes where stale fuel will wreck the piston, and mixed fuel doesn't last as long as straight fuel..

 

Running your motor on the cold side is difficult but is probably one of the biggest factors in safer operation. Some faster planes have had little problem.

 

Any motor that runs rough is doing it for a reason and it should be investigated, not just keep flying it. Why hasn't any one run colder plugs? It seems an obvious thing to try under the circumstances. If it doesn't soot up on long taxying it won't cause any trouble at other times..Nev