Some Food For Thought for Tinkerers

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Discussion Overview

The discussion revolves around the dangers associated with turbine engines, particularly focusing on a specific incident involving a GECF680A2 engine on an American Airlines 767. Participants explore the implications of turbine disc failures, share personal experiences, and express concerns about DIY turbine projects.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants express concern about individuals tinkering with turbine engines, highlighting the violent nature of disc ruptures and the energy contained in rotating hardware.
  • One participant questions whether the failure was a near-idle incident, suggesting that more damage would be expected if the engine was spooled up.
  • Another participant shares a personal anecdote about witnessing a small jet engine running at high RPM, reflecting on the potential dangers of such experiences.
  • There is a discussion about the size and weight of engine rods, with one participant sharing their experience of a rod failure in a different engine.
  • Clarifications are made regarding the specifics of the incident, including the path of the fractured disc and its impact on the aircraft structure.
  • Participants discuss the throttle settings during the incident, with one noting that the aircraft was likely not at ground idle during maintenance runs.
  • There is a mention of a past accident involving a turbine disc that affected flight control systems, indicating the potential severity of such failures.
  • One participant expresses relief that if they were close to the incident, they would not have been aware of the danger.
  • Casual conversation about military helicopters flying by, indicating a shift in topic but maintaining a connection to aviation.

Areas of Agreement / Disagreement

Participants share concerns about turbine engine safety and express personal experiences, but there is no consensus on the specifics of the incident or the implications for DIY projects. Multiple viewpoints and uncertainties remain regarding the nature of the failure and its context.

Contextual Notes

Some assumptions about the incident's conditions, such as throttle settings and the nature of the failure, remain unresolved. The discussion includes personal anecdotes that may not directly relate to the technical aspects of turbine failures.

FredGarvin
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I always cringe when I see posts by people who are playing with turbines in their garage. So, whenever I come across something like this, I like to share.

Case: A GECF680A2 on an AA 767. Looks like an HPT disc failure.

http://www.flickr.com/photos/lafd/159079755/in/set-72157594153722446/

Disc ruptures are violent failures. It hopefully gives one an appreciation for just how much energy is contained in rotating hardware.
 
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FredGarvin said:
I always cringe when I see posts by people who are playing with turbines in their garage. So, whenever I come across something like this, I like to share.

Case: A GECF680A2 on an AA 767. Looks like an HPT disc failure.

http://www.flickr.com/photos/lafd/159079755/in/set-72157594153722446/

Disc ruptures are violent failures. It hopefully gives one an appreciation for just how much energy is contained in rotating hardware.

:eek:

Well, I hope nobody is playing with a turbine off of a 767 (or any large plane) in their garage anyway...

Those miniature turbines for go-karts and what-not are still pretty cool though. :wink:
 
Good post, Fred. Was that a near-idle failure? I would expect a lot more damage from something that was spooled up. If I remember correctly, back in the late 60's/early 70's a commercial liner shelled a disc (Detroit Intntl?); it went right through the cabin.
 
Thanks for sharing that Fred. To be honest I wasn't that shocked, I wouldn't have been surprised at seeing a lot more damage (you too I suppose), but if it's enough to put some healthy fear into a DIY turbomachinist then it's a job well done!

I remember standing with my nose up against a (small) jet engine running at 70,000 rpm at uni, probably wouldn't have been quite so intrigued if I'd seen that photo beforehand!

Would like to post you guys photos of the damage a 64 litre reciprocating engine does when it throws a rod, but I might get sacked...
 
Having once put a rod through the pan of a 283, I daren't even imagine what that must be like! :bugeye: How big/heavy is one of those rods?
 
Danger said:
Having once put a rod through the pan of a 283, I daren't even imagine what that must be like! :bugeye: How big/heavy is one of those rods?


I suppose about 12-15lbs (note my conversion to USian for you!) and about 18"-20" long. The engines fire hard too.
 
brewnog said:
(note my conversion to USian for you!)
Thanks, but Canada is metric. (I still tend to think in imperial, though.)
 
As a small note...I don't know if anyone noticed, but the first two pictures I posted were of the fractured disc penetrating the #2 engine on the opposite side of the aircraft. The failed disc came from the #1 engine. The disc went right thru the fuselage.

Brews,
I guess you could rest easy knowing that if you were that close and something did happen, you would have never known it.
 
Danger,

I haven't seen anything stating at what throttle they were at. The aircraft was in a maintenence dock doing ground runs, so it is a very safe assumption that it was not a ground idle when it happened.

I'm not so sure about the incident you are referring to. The only other major accident I can recall was the flight that crashed at Sioux City after a thrown tubine disc ruptured all of the fligh control hydraulic systems.
 
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Thanks for the clarification, Fred. That makes more sense. I thought that the picture showed the disc not quite making it out of the engine case. I got so engrossed in looking at your in-post photos that I forgot there was a link above them.
 
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If that failure happened in the air, bye bye airplane.

BTW, two chinooks flew by my house the other day fred.
 
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cyrusabdollahi said:
BTW, two chinooks flew by my house the other day fred.
Really? I wonder where they were from. There isn't any regular Army posts near you. It may have been reservists or 160th. Are you sure they weren't CH-46's in stead?