LGM Graphix

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Remember when turbine manuals all had the picture that showed you the "danger zone"? I haven't even looked at a manual for a current engine in years, but in all honesty, I don't remember seeing that picture in manuals any of the turbines I have owned with the exception of 2, RAM, and AMT. They always showed you the danger zone is I believe it was 20 meters to either side of the jet, 20 meters behind it, and 1 meter in front. But then I remember when every kit sold also came with a brochure for MAAC or the AMA with contact info and why you should join.

mistermnkim

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Any pics of the airframe damage?

bevar

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Yep...a few.

Beave

AndyAndrews

holy crap Boli... that is some incredible forces working there. I hope no one got hurt.

PaulD

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That A380 failure could have been so much worse. The fact that the crew managed to land that plane safely with only partial flaps and, only 3 engines running and only 2 controllable on 1 wing is amazing. Add to that the fact that none of the debris actually went thru the fuse is also amazingly lucky. Those holes in the wing are pretty large...

http://blogs.crikey.com.au/planetalk...near-disaster/

PaulD

skyhawknut

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Here is is on fire.

flycatch

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Just something else to give jets a bad reputation. Have you ever seen a helicopter shed its' rotor blades.

David Gladwin

That A380 is now back in service, 18 months and 150 M dollars later, paid for by insurance, Airbus, Qantas and, of course, Rolls Royce.

It seems the respect for the A380 by crews and engineers is at even higher levels following this incident, its systems redundancy and structure allowed it to survive what for some aircraft could have been catastrophic.

It'll be interesting to see what new orders for the big Bus, (and the 747-800 which is struggling) if any, are announced at Farnborough, next month.

Someone mentioned complacency. That is generally considered, by professionals, the biggest hazard in air safety these days, created by extreme reliability of modern equipment, and exists big time in model jet aviation., no doubt for the same reasons. I see the "safety matters" thread on RCU has been deleted (it went for over a year without a single contribution) yet every other branch of aviation has safety as the cornerstone of their operations. Why do many jet modellers (by no means all, many other guys are really sharp) think they know better than the rest of aviation, or just don't care ?

Turbine blades separating , nothing new, had it happen in flight on a BA VC10 in 1976 when a Conway let go a lot of blades from the LP wheel, just after take off (getting my full and undivided attention !) and many of us remember the Vulcan at Scampton. Going to full power for take off, No 1 engine, Olympus 200, HP turbine wheel came off , went through no 2 , big bang, wheel then sawed its way through the fuselage fuel tank, into no 3 engine, another big bang then into no 4 before continuing its journey across Lincolnshire. The resultant fire left only a nose section and four jet pipes plus a pile of ash the shape of the Vulcan on the R/W threshold !

All crew escaped including an air cadet on an air experience flight (last seen running for his life, parachute trailing behind him ,) .

These engines are wonderful pieces of precision engineering but, like fullsize engines , deserve our full respect at all times, or sooner or later they WILL bite us.

Regards,

David.

Gordon W

This thread reminds me of when my car's flywheel exploded.

The clutch had been slipping because of an oil leak through a bearing seal, so I decided to burn off the oil by slipping the clutch against the brakes.

Things were going well when suddenly there was a bang, engine revs soared, smoke and steam issued from under the bonnet, there were lots of rattles, a cat ran across the road in fight, the burnt clutch smell was indescribable, and I switched off the engine darn quick.

On inspecting the damage, here's what here was:

1. Bonnet liberally dented from the inside.
2. The entire clutch bell-housing had fragmented as the flywheel went through it.
3. Chunks of flywheel were embedded in the rear firewall of the engine compartment (it was a transverse-mounted engine) immediately in front of the driver's seat.
4. The battery was cut in half and battery acid was bubbling away as it dissolved the concrete driveway.
5. The "cat" which had run away turned out to be 1/2 the flywheel, which had bounced across the road to embed itself in the garage door of my neighbour across the road, knocking the door back off of its tracks.

This was back in about 1983 and I fixed the car for about £30 using parts from a breaker's yard. I don't think the fix would be just as easy with modern cars.

Woketman

My Feedback: (6)

Something here that I cannot understand guys. IIRC, the KJ-66 design (and this looks like a KJ-66 derived design, but maybe not) had the turbine wheel axially, at the same station as the thick steel ring that the tail cone bolted to. This was not a coincidence, but intentional. The aft thick steel ring was intended to act as a containment ring to prevent just such a shrapnel occurrence such as this. I think it even stated that in the old RAM manuals.

Many of us that were flying turbines in the late 90s had our share of RAM failures. Most typical were the rear bearing failures on the RAM 1000. The bearing would fail and the wheel would contact the housing and disintegrate. But I never saw something like this happen.

So what engine is this? Is the turbine wheel in front of the tail cone mounting ring? Or is there some other mechanism that allowed/forced the debris forward to exit in front of said ring?

luv2flyrc

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Looks like a P-80SE to me

Mike

bcovish

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What brand or size of turbine has nothing to do with it. This can and does happen to all brand of turbines. So let's not turn into a brand bashing thing. Again, the purpose of this thread is about complacency and safe operation of our models.

quote:

These engines are wonderful pieces of precision engineering but, like fullsize engines , deserve our full respect at all times, or sooner or later they WILL bite us.

Henke Torphammar

True about not starting any brand bashing... you are probably also right that it CAN happen to any engine as nothing is impossible but it does matter how you design the engine Not all engines are designed like this unit even though it is the most common design on the market.

Woketman

My Feedback: (6)

But Bob, that is my point: perhaps it IS (to a degree) about brand or size!!!! My point was that the KJ-66 design is/was such that there is a "containment ring" around the turbine wheel that should prevent turbine wheel fragments from exiting the engine orthogonally with high kinetic energy. That is exactly why the thick ring was positioned around the turbine wheel.

So why did this happen to this particular engine? Did the entire shaft somehow move forward such that the wheel was no longer inside the thick ring? Has the design changed? Did something else happen? Our RAM 1000s failed there aft bearing/turbine wheel all the time but I never saw one do this!!!!

DelGatoGrande

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basimpsn

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Looks like the blades went backwards pass the NGV, even standing in front this plane is not safe. Now I see why AMA band engine reverse thrust

P.S Broken main shaft ?

RCISFUN

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Jet Central also covers this topic

AndyAndrews

I believe so, the rear fan was detached and it was just a lose disk with all of the blades sheared off at the root. There was a 5 foot long blow torch comming out of the jet for about 3-4 seconds when it happened.

bcovish

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JetCat also covers this on page 9 of their manual.

HarryC

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It's in all the Wren manuals too, with a diagram showing the danger zone to avoid.

DocYates

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A couple of years ago I had the displeasure of standing near another brand of engine that had a catastrophic failure on a test stand. This one started out as some type of electronic failure that progressed to a runaway fuel pump that cause the engine to over rev and ultimately to a bearing failure with a huge fire and some dirty underwear. I will admit there had been some complacency on both myself and the owner's part up until then, but from that day on every time I start a turbine I assume it is going to fail and keep my extinquisher nearby and keep bystanders out of the danger zone. You have to respect these engines.

Shaun Evans

Boli,

When did you start writing ads for Greyhound?!? Geez that's some scary stuff, statistical unlikelihood or not....

rcjetsaok

My Feedback: (7)

Mark,

I know what you are saying... I was surprised of this damage as well when I saw it happen. I thought the Turbine Wheel was further aft in the "Meat" of the case. Where these openings are seemed forward of where I thought/envisioned the wheel was located. Looking at the engine it appeared the shaft sheared at the turbine wheel. The nut was gone and the shaft was sheared clean with no threads left. the wheel was completely loose in the rear section. In my opinion, the shaft failed, the wheel departed, and that's when the blades were all sheared off. The wheel was in tact with no blades left on it and loose in the tail cone section. When the shaft failed, the entire assmy must have gone forward enough for the shrapnel the exit the thin part of the can where the pictures show. The compressor wheel also was damaged. I saw a RAM 1000 explode on a test stand years ago, the turbine wheel contacted the NGV's due to rear bearing failure. The failure was "As Advertised"... All shrapnel came out the tail cone with no damage the the case. The wheel was contained in the containment ring section upon failure. In this case, I think the shaft broke, and allowed the rotating assmy to go forward and then it came unglued.


Danno

Woketman

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Understood Danno. Yes, your description of the RAM 1000 failure mode was pretty much the same as all of them that I saw.... and that was about four!!!

DavidR

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The shaft was broken, allowing the wheel to shift backward.

DR