Are Jabiru engines really that bad?

[Sapphire]

skeptic said: What I am trying to get across is that we should not be continually pushing the idea that engine failure means death, it is insinuated regularly on these forums,

 

Do you read accident reports at all? Death is bad enough and injury sounds like a relief that someone got away with it; until you read they are so crippled that even feeding themselves is a lost option. They gambled their engine wouln't fail and lost. My last ultralight would go down into tiger country at about 60 kts [with skill] and crashing into a tree at that speed would be like crashing with your car into a fallen tree on the freeway at top speed [no braking] Get real.

 

 

[Guest nunans]

And cars are built alot heavier than any ra aircraft and they can afford the extra weight of crumple zones, air bags, safety cell cabins, metal panels etc. They are built with a crash in mind. ultralights are doing thier best just to fly nicely with the given weight and horsepower. They are not really designed to withstand a collision with trees or a hill.

 

 

[cscotthendry]

For sure. But if you're flying responsibly then the actual percentage of time that you spend over tiger country should be minimal, then if you have an engine out, say, every 300 hrs the chances that you can glide to a safe landing have to be pretty good I would have thought.Scott, I was not trying to twist your words and I don't believe I did. What I am trying to get across is that we should not be continually pushing the idea that engine failure means death, it is insinuated regularly on these forums, sometimes flipantly , sometimes seriously. An inexperienced pilot, which most of us are, has enough on their plate in the almost inevitable event of engine failure and shouldn't have the added pressure of thinking this is the end. I know panic would be hard for me to resist if I thought that were the case.

So apologies Scott if you thought I was trying to be abrasive or a smart axx, that was not my intention, just trying to make a point.

 

regards Bill

Bill: OK I'm pulling my head in now. No offense taken. But my intention was to say that when I gamble my life (as I willingly do for flying) I want the odds as long in my favour as I can get them. From all that I've read and heard about Jab engine failures, my choice is to go with a Rotax driven fan up front.

 

 

[facthunter]

There would only be a small percentage of the time where an engine failure would definately kill you. You could anticipate serious injury in more situations.. Flying slow improves your chances. A fast plane is more hazardous.

 

Mid air collision or in flight fire, I see as very serious situations to be in. Planes are not built to crash in but it is surprising how many people do survive something which you would think they wouldn't, impact wise. Nev

 

 

[motzartmerv]

Yep. Its all about the physics. The energy you absorb is what kills you. The total energy can be derived by the formula MV2. Mass X Velocity squared.

 

600 kilo aeroplane doing 100 kts = 6000000 joules

 

600 kilo aeroplane doing 50 kts = 150000 joules

 

note that by halving the speed, you have reduced the energy by a factor of 4, not just half. Its the inverse square law in action and is what kills you or sends you home with a story to tell.

 

During a crash the energy is dissipated very very quickly, so the idea would be to NOT fly into a solid object directly. Any time on the ground be it grass, bitumen, corn field, beach, before you pay all the energy back to the bank in one go, ie, (hit something), the less energy involved and the more likely you are to survive. This is the scientific reason why vertical arrivals are rarely survivable. The energy is too high and payed back to the bank too quickly. Where as the same Velocity paid back over a distance of (during deceleration) 20 meters is much more likely to be survived.

 

 

[motzartmerv]

Ahhh..Newton... Is there anything he cant teach us...lol

 

 

[facthunter]

The Origin of the Universe?

 

I use Newtonian physics all the time in flying. It has always been a passion of mine.

 

Try not to hit anything solid. Groundloop if you are going into a wire fence in any pusher or glider or consider it anyhow. Turn into wind. It won't work the other way. (If there is a X-wind)

 

Old advice was to go between two trees and hit them evenly . This takes the wings off and slows you gently. Might get rid of the fuel tanks too. Always land into wind. It's the groundspeed that hurts. Nev

 

 

[motzartmerv]

Ok. Granted, the origin maybe not, but evrything from a few hundredths of a second after the beginning he can help with;) with the exception of things smaller than aeroplanes hehehe. I'm with you, I love using him to help describe an understand what going on. It's not for everyone though, some students would run for the hills if you dared to write a formula on the board.. ;)

 

 

[Guest Error404]

Engine failures are about when and not if. If you adjust your flying to suit that philosophy you will survive a long and happy life.

 

 

[facthunter]

Nobody "survives" any kind of life. I'm only being funny. You meant "to have" a long.and....

 

. Engine failures. You never know when you will have one. Most think that the plane just dives into the ground, but we know they still fly, don't we? Nev

 

 

[Gnarly Gnu]

The Origin of the Universe?

Newton understood that also. A very wise man indeed.

 

On topic I'm fine flying with the Jabiru engine and think that there are many, many good parts of the Jabiru engine that very rarely give trouble, however currently I suggest TBO is going to be around 1000 hours realistically. But it is let down by 2 or 3 areas that do break. Just keep hoping the factory would release a significant update that would address the latter parts. In a non-certified aircraft there may be the option to modify the engine, add EFI etc which works a treat I understand.

 

 

[Guest Error404]

Here is something to ponder.

 

How many fatalities have their been behind Jabiru engines versus Rotax and then factor in the number of Jabriu engines versus Rotax out there and indeed you will be surprised.

 

 

[motzartmerv]

mmm...Lies , dam lies and statistics.. Bet there's been many more deaths behind a rolls royce merlin than both put together.. Your point is?

 

 

[fly_tornado]

The constant repairs and rebuilds that a sizable numbers of owners have gone through is deal breaker for me.

 

Who wants to keep putting their hand in the pocket every time you fly?

 

 

[facthunter]

Is there another way unless you are paid to do it. Nev

 

 

[Ultralights]

Jabirus have a high survivability in an off field landing due to the strength of the airframes, nothing to do with the engine. The engine just determines how often you might have to test that airframe.

 

 

[Guest Error404]

That's right ultralights, it's what I was thinking. I don't even know of an Austrlian Jabiru fatality despite all these engine failures everyone is referring to. Goes to show that it's not necessarily safety related although I dare say there have been many write offs.

 

 

[Guest Maj Millard]

I can think of several. How about the two gentlemen from WA who picked up a new one at Bundy, and didn't make it pass the ranges before coming to grief ???...............Maj...

 

 

[Guest Error404]

That was CFIT if its what I'm thinking of. I realise that i did know about that one but in the back of my mind i didn't include it because its not in any way relevant. I believe it was on its way to Wangaratta flying school with a very experienced pilot, is that the one you are referring to? Not immediately aware of any others. Gosh that one was a long time ago in ultralight years if that's what you are referring to. I can very quickly think of a lot of Rotax fatalities.

 

 

[Powerin]

I have been reading these forums for a while now and there seems to be a lot of Jab bashing going on. Now I have noticed myself in the RAA Members Market you see a lot of airframe 400 hrs new motor type listings. I have done a couple of hours in a jab and didn't mind flying it at all and there seems to be quite a few around that are affordable. So

 

1. Are they really that bad ?

 

2. If they are as bad as people make out what do you all think causes the issues they have and are the problems manageable?

 

3. Do they have any other big problems

 

All opinions welcome I would love to here from Jab drivers seeing they trust these things with there life.

 

Thanks

 

Marc

Here's a bit of research I did in response to a question about CASA records. Also see my follow up post below this one regarding the numbers of Jab and Rotax engines on the CASA and RAAus registers. Hope it adds something to you own research.

 

http://www.recreationalflying.com/threads/jab-down-again.50745/page-2#post-251642

 

 

[Guest Maj Millard]

Are you absolutly sure it was CFIT Error 404...did you see an offical report ??....................................Maj...

 

 

[Guest Error404]

I did. It was an article in a magazine, quite detailed in fact far more detailed than what we get these days. It clearly talked about pressing on, the conditions, pilot (s?) and had pictures of the crashed aircraft in detail. From memory smacked into the side of a hill in cloud. If I'm not mistaken Wangaratta then bought a Gazelle for training because of the stigma of the Jabiru, even years later. In fact it may have even been an instructor from there or the CFI. I'd like to know more now.

 

 

[Guest Maj Millard]

Well mate an article in a magazine is just that. There were rumors around that they were on top, and suffered an engine failure, which resulted in the mountain encounter. Pretty damn hard to prove an engine did or did not fail when it's only an inch thick !...there are others too, I'm thinking, Jabs go back well over 25 years now and so do I.!..................................................Maj...

 

 

[Guest Error404]

Understood powerin, I fully get those stats, I just find it interesting that those stats don't match fatalities

 

You are grasping at straws Maj. You're telling me that you are theorizing that an engine failed all those years ago and that's what caused the crash when there is zero evidence to suggest this other than some rumours?

 

 

[Guest Error404]

Found it

 

http://www.jabiru.com.au/jabiru-articles/1999/4/1/plane-crash-claims-2-lives/

 

Scarce on details but certainly some bad terrain.

 

Some say if you are going to fly over solid cloud you may as well be in it.