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CASA - Draft Proposal for Jabiru Aircraft


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IFA or IVP (take your pick) allow you to actually have available on the runway for take off the engine's max hp. Even a ground adj prop is not going to go anywhere near that if it is set so as not to exceed max continuous hp in straight and level flight. ANd you can have max continuous hp for climb and whatever you like for cruise - speed or economy.

 

IVP will set you back between $5k and $8k and add between 5kg and 9kg depending on type and whether CS or not. The weight is not an issue because what it gives you in fuel economy you can save in fuel weight. Cost is just a matter of how rich your parents are 054_no_no_no.gif.950345b863e0f6a5a1b13784a465a8c4.gif.

 

 

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It appears to me that this thread has gone waaay off track..as so often happens on this forum...

True. Just filling in the lull before the storm.

After CASA makes their next announcement it will, no doubt, get back on thread pretty quickly.

 

 

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From a Mate of mine ...One guy is a very experienced pilot, he has a GA plane as well as his home-build, he says that the Jab

 

is a great motor to fly behind and he's happy to stick with it - even though he

 

has had to strip it down after only 100 hrs already!

I guess it goes without saying that some people are very easily pleased. I know what I'd be saying if I had to strip my engine down after 100 hours, and it's not printable here.

 

 

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Geoff,I 100% appreciate your comment, but it does not remove in anyway the fact that many people just don't have that sort of money.

 

Makes me hope and support CAMit to a decent result even more.

It amazes me to think that someone can afford 100k plus for but can't afford an extra 10 to 15% for safety.

 

I would think that if the budget was that tight, than maybe that person could not afford the maintenance required to keep and airplane safe or certianly not be able to afford a couple of rebuilds down the road. The difference between an 80 hp rotax and an 80 hp Jab on the figures I have got would be less than 10% of total cost and less than a replacement motor if the worst happens.

 

As I have said I am not yet convinced that it is all the engines fault but while there is doubt, I think safety is far more important than dollars. Ie if you cant afford to do it safely then you actually cant afford to do it.

 

Cheers Geoff13

 

 

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We are going on some very imprecise assertions at times here. Tell us what was wrong with the engine, to HAVE to strip it at 100 hrs, and why it (they think) was like that. People "blueprint" lycomings to make sure they are in optimum shape, in some circumstances, from new or very low hours. The motor might have exceeded the specified temps. Who knows? . A lot of the problem is in the installation regarding cooling.. Nev

 

 

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I guess it goes without saying that some people are very easily pleased. I know what I'd be saying if I had to strip my engine down after 100 hours, and it's not printable here.

My level of displeasure, if it were my engine (irrespective of brand) , might depend on how those hours were achieved and over what span of months/years. If I was flying 3 or 4 hours a week my anger level would be much higher than if I was flying 1 or 2 hours a month. Whether I had adequately inhibited between layovers it and whether I had refreshed the fuel might also have something to do whether I was more p!ssed with the engine or or with myself for unsympathetic operation of the engine

 

 

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For years now I have been pushing the need to do something when leaving engines idle for as little as two weeks. There is info on the CASA site, about inhibiting motors. I have NEVER had ONE person respond and indicate they did anything with their motors. The worst thing you can do is wait in the clubroom talking after flying and then start the engine from cold and taxi for a hundred meters or so and then have it in the hangar for a time. Rust will commence almost straight away in these circumstances. The oil rings wipe virtually all oil off the surface of the cylinders and the combusted fuel produces water contaminated with acids. Nev

 

 

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I've finished up with a few seized engines on the farm, but I'm still too lazy to drain the fuel tank and throw the fuel away on my ten or so engines, let alone inhibit them.

 

Twenty years of so ago, you could leave them for a year and then start them every season (I've mentioned a couple of 1950's tractor engines still in good working condition), but today I'd have to say I've had it with the oil companies, and for any new small powered units I'm buying electric. It's cheaper to do a job over three days with three charges than to empty all the fuel tanks round the place and throw the fuel away.

 

However, FH, with an aircraft what you are saying is exactly correct, and not only that, but I'd drain the carby and the fuel tank and take it home for the ute. I just can't believe how our authorities have quietly turned their backs while our fuel standards were being watered down.

 

 

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For years now I have been pushing the need to do something when leaving engines idle for as little as two weeks. There is info on the CASA site, about inhibiting motors. I have NEVER had ONE person respond and indicate they did anything with their motors. The worst thing you can do is wait in the clubroom talking after flying and then start the engine from cold and taxi for a hundred meters or so and then have it in the hangar for a time. Rust will commence almost straight away in these circumstances. The oil rings wipe virtually all oil off the surface of the cylinders and the combusted fuel produces water contaminated with acids. Nev

Nev, Ian Bent had on display at Temora a device which injected a mist of oil into the cylinders as the engine was being shut down to aid in inhibiting the engine. Seems like a very sensible mod and one which I will be fitting to my engine.

 

 

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It's a complexity but necessary. Pumps and mowers I just squirt WD into the mufflers a short while after shutting them down. If you don't you suffer exhaust valve stem/guide rusting and seizure. This is a problem with 4 stroke outboard motors too. Making sure the aircraft engine is fully HOT (normal operating temps) before shutting down reduces the amount of moisture left in the engine but it still has acids in the products of combustion. Nev

 

 

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The oil rings wipe virtually all oil off the surface of the cylinders and the combusted fuel produces water contaminated with acids. Nev

Not in a radial! The longer it's standing there, the more oil coats the cylinders and pistons!003_cheezy_grin.gif.c5a94fc2937f61b556d8146a1bc97ef8.gif

 

 

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Only the bottom ones. The older motors used a lot of oil due to the oil rings used THEN. Today we tend to use far more effective rings, ( perhaps inappropriately). The Jab seems to run very dry. Some builders of Gypsy Majors use them too now, and some of them don't last as well as they used to. A bit of extra oil helps keep blowby figures down in hot running aircooled motors..Nev

 

 

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Dont know whether this would help.

 

I have old carpet on my rubble hanger floor. I noticed last year that when removing the cowl for inspection that there was considerable moisture on the engine.. guess that it would also be interanly contaminated.

 

I have been thinking of laying plastic sheeting down under the carpet, this should stop the moisture from rising.

 

Any body done this?

 

Phil.

 

 

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It appears to me that this thread has gone waaay off track.....

You are right, but I have to respond that I have got something from many of the posts on this issue.

 

 

 

However I do think that some may have been sucked into a type of feeding frenzy about J engines.

 

 

 

While there appears to be some issues that need addressing, and I like the fact that Jabiru themselves have been (re)focussed on addressing any issues that are clearly demonstrated, it is equally a fact that some owners have achieved good to great results and are satisfied, plus I know of several aircraft that have circumcised the continent without any issues.

 

 

 

After J aircraft have given such sterling service in Flying Schools over numerous years it is, in my opinion, a tad over the top to now be saying that it is an unacceptable risk to send your son or daughter solo in such an aircraft.

 

 

 

So I like the fact that CASA have given Jabiru a prod, but as usual, they appear to have been ham-fisted in that they may have also blindsided most owners and FTF's using such aircraft. Collateral damage is unacceptable on an issue such as this and I don't understand why CASA couldn't have been more targeted in their actions. CASA would do well to learn subtlety and how business is done out in the real world, where such issues can often be addressed, progressed and resolved more on the QT.

 

 

 

Regards Geoff

 

 

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The internal moisture is from a different source. Air can not easily flow through a stationary motor. Both valves have to be open at the same time and this is not a particularly common event in the cycle. About 60degrees out of 720. Nev

 

 

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The internal moisture is from a different source. Air can not easily flow through a stationary motor. Both valves have to be open at the same time and this is not a particularly common event in the cycle. About 60degrees out of 720. Nev

 

 

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Reading the responces that are contained in the Dropbox link a few pages back, it appears the respondents didn't read the part from CASA;

 

While responsive comments of any kind may certainly be submitted, the most helpful and relevant responses will relate to the nature and scope of the proposed operational limitations, and such alternative operational limitations as might arguably be more suitable in all the circumstances. In making such alternative proposals, it will be useful if clear reasons for those alternatives are provided.

 

Most of the replies are very emotive with no supporting information or facts and will most likely be disregarded by CASA.

 

 

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Hey Rat. Whilst it doesn't behoove me to take the piss, I'd be truely amazed at an aircraft (or anything else for that matter) that had 'circumcised' a continent. Large undertaking I'd guess. 012_thumb_up.gif.cb3bc51429685855e5e23c55d661406e.gif

 

 

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How can you decide whether your engine is safe to take passengers?

 

First, buying a Jabiru and operating it as advised isn't enough. True earlier true now.

 

Do you monitor CHTs and EGTs accurately for all cylinders? Did any ever go too high?

 

Do your flywheel bolts have any aluminium under them?

 

Problem with through-bolts? Unless the bolts are faulty you have an unexplained problem.

 

Hydraulic lifters? Introduced a new set of problems. I don't know if they cause failure in flight but I hear they cause nightmares on the ground.

 

Because you don't know your Jabiru engine is unsafe you can't tell your passengers it is safe.

 

 

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Had a very interesting conversation with Ian Bent yesterday. He almost convinced me that they are safe, and he gone even closer to convincing me that they can be made safe. It does seem a pity that the left and right hands can't work together.

 

Cheers Geoff

 

 

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