Incident at ISP

Boris Badenov said:
Someone was wondering out loud whether he might have started up with the MOR at max blast. Makes as much sense as anything I've heard.
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Supposedly this experimental aircraft came out of build with the MOR safetied in the wrong position then attempted an engine start. sorry for the potatocam pics, they’re the only versions I’ve been able to find online. Notice after shutdown the hot section glowing cherry red.


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Fuel control runaway on start? I'm not familiar with the Pilatus, but know in some pt6's that if the tiny plastic spline in the FCU shears that you need to be handy with the condition lever immediately.
 
NOGUFFCHET said:
Fuel control runaway on start? I'm not familiar with the Pilatus, but know in some pt6's that if the tiny plastic spline in the FCU shears that you need to be handy with the condition lever immediately.
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PC12 fails to the minimum fuel flow stop.

That should be something like 48% NG sea-level standard day if memory serves?
 
NOGUFFCHET said:
Fuel control runaway on start? I'm not familiar with the Pilatus, but know in some pt6's that if the tiny plastic spline in the FCU shears that you need to be handy with the condition lever immediately.
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Could be. When I was still working mobile I was working on a LR35 and after we'd changed an engine and took it out to idle/leak check it, it started and after it started it didn't even think about idling, it started spooling up to T/O power, luckily we got it shut down before any damage was done. Turned out to be a bad DEEC, which was odd because all we'd done was input the "new" engines info. Swapped the DEEC with the other engine and it ran fine. Sometimes in MX strange things happen. We were in Scottsdale so our proximity to Honeywell only required us to extend our 12 day trip out one more day to change the offending computer and finish the engine runs before heading home, and yes it was summer and it was hot. Strange things do happen occasionally that are completely unexpected. Never take anything for granted after MX.
 
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DropTank said:
Where the engine is located so far from the CG, it's like balancing a broomstick



That's my guess.
Someone kicked the power lever and the engine went ape• on startup.
If the tarmac was icy and/or the pilot reaction was slow then crunchie happens
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Does no one else give the throttle(s) a quick tug rear before start to make sure they are against the stops?…to say the very least, starting in ground fine is a neat way to hot start a pt6.

and yes Im aware manipulation of the throttle with the engine off can cause binding in the block, but thats only across the detent ranges afaik…so a quick tug shouldn't hurt right?
 
Boots2Wings said:
Does no one else give the throttle(s) a quick tug rear before start to make sure they are against the stops?…to say the very least, starting in ground fine is a neat way to hot start a pt6.

and yes Im aware manipulation of the throttle with the engine off can cause binding in the block, but thats only across the detent ranges afaik…so a quick tug shouldn't hurt right?
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PC12's start feathered.
Starting in flight idle is really no big deal and would certainly NOT cause an airplane to launch forward like that.

The video is definitely max power. I would like to know why the condition lever wasn't place into cutoff at the first sign of trouble.
And if that didn't work, the firewall shutoff.

Pilot had the good sense to try to avoid the Hawker.
 
Yea i was referring to the throttle not the prop lever. (Although Id run across those as well)

Only time a pt6 should start unfeathered afaik is for cooling say on a bat start. Though admittedly Iknow nothing about pc12s.

Like you said, it seems odd an immediate shut down didn't occur, maybe there was a mechanical issue.
 
DropTank said:
PC12's start feathered.
Starting in flight idle is really no big deal and would certainly NOT cause an airplane to launch forward like that.

The video is definitely max power. I would like to know why the condition lever wasn't place into cutoff at the first sign of trouble.
And if that didn't work, the firewall shutoff.

Pilot had the good sense to try to avoid the Hawker.
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Or drop it into beta or something. Is it possible this was a maintenance run? I know the cowling was off when it came to rest, I thought it was part of the crash or maybe the firefighting effort but it almost looks like it’s already off in the video?
 
I not familiar with a FCU failure that would put it into max power.
Most failures would be a P3 leak that would cause a roll back.

and a MOR lever movement of that magnitude would likely china syndrome the engine before it made takeoff power
 
DropTank said:
I not familiar with a FCU failure that would put it into max power.
Most failures would be a P3 leak that would cause a roll back.

and a MOR lever movement of that magnitude would likely china syndrome the engine before it made takeoff power
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Could be a stuck torque block in throttle rigging.
 
“Should”
Yup…also…brakes held. But I’ll quit armchair quarterbacking for now. It will make it much less awkward if I screw something major in the future.

Im a firm believer there are many many many more gifted pilots than myself who somehow ended up a smoking hole…one bad day, tired brain, and the right set of circumstances, we will have an “Oh xxx” thread for it.
 
Boots2Wings said:
“Should”
Yup…also…brakes held. But I’ll quit armchair quarterbacking for now. It will make it much less awkward if I screw something major in the future.

Im a firm believer there are many many many more gifted pilots than myself who somehow ended up a smoking hole…one bad day, tired brain, and the right set of circumstances, we will have an “Oh xxx” thread for it.
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I never had a problem with pondering an accident/incident.
It's a good mental exercise.

and in the event that I do bent an airplane I'd likely Monday Quarterback more that anyone else.
 
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