Windmilling damage?
Joined: Jan 2008
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From: All at sea
With the disclaimer that all the following may not be entirely accurate (as it was not my airline wot dun it). A BAE146 was being ferried with an engine inoperative and fan not locked. For whatever reason (maybe to use the TMS?) the Captain did not keep the thrust lever of the dead engine in fuel cut-off. They encountered ice, so selected ignition ON. Windmilling damage? If the resultant explosion was categorised as windmilling damage, or finger trouble, I know not.
Joined: Dec 2002
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From: UK
Mach, not aware of that particular version, but at least one operator experimented with locally derived procedures to their detriment.
An issue with the 146 engine was the geared fan; the fan shaft / turbine could windmill relatively fast, whilst the core - oil pump, would be slower or even stop.
As I recall, after an in flight shutdown, if the core stopped or was below 7% the engine should not be relit, because of potential un-lubricated bearing failure.
The fan had to be secured for ferry flights.
An issue with the 146 engine was the geared fan; the fan shaft / turbine could windmill relatively fast, whilst the core - oil pump, would be slower or even stop.
As I recall, after an in flight shutdown, if the core stopped or was below 7% the engine should not be relit, because of potential un-lubricated bearing failure.
The fan had to be secured for ferry flights.
Joined: Feb 2007
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From: Edinburgh
146 Lockout
If you were to lockout a 146 engine, you locked out the fan, with a bar across the turbine, the core with a locking pin, disconnected the igniter boxes and took a lead off the start contactor.
The story that Mach refers to did happen, just a couple of wee details are different. The fan was locked, the core wasn’t, the igniters were not disconnected. So the core drove the fuel pumps etc, as it windmilled it pumped fuel into the combustor. I heard at the time the captain liked to keep all 4 throttles in a line like usual.
The rest of the story turned out just as Mach said…..
The story that Mach refers to did happen, just a couple of wee details are different. The fan was locked, the core wasn’t, the igniters were not disconnected. So the core drove the fuel pumps etc, as it windmilled it pumped fuel into the combustor. I heard at the time the captain liked to keep all 4 throttles in a line like usual.
The rest of the story turned out just as Mach said…..
Last edited by clarkieboy; 11th May 2024 at 08:51. Reason: Spelling…
Joined: Jul 2013
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From: Everett, WA
Yea, that's not a 'windmilling engine' damage - that's basically an attempted in-flight start with a locked low rotor (fuel on, ignition on, fan not turning). That's an almost guaranteed bad outcome (regardless of the engine type)...
Joined: Apr 2008
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From: UK
Joined: Jan 2007
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From: UK
I was on Beverleys in the sixties.
We'd been stuck in Lagos for a week or so with an engine failure, and we were going to Kinshasa via Douala in Cameroon. Unfortunately, having refuelled, the number four wouldn't start because of a duff starter motor. I explained to the Tower that we'd taxy out on three and get the no4 to start on the roll, and if it didn't start we'd taxy back and shut down.This was baffling to the Tower who hadn't got much English and reluctantly agreed it. Fortunately the No4 started and we were airborne (I didn't use the word 'moulins' ) !
We'd been stuck in Lagos for a week or so with an engine failure, and we were going to Kinshasa via Douala in Cameroon. Unfortunately, having refuelled, the number four wouldn't start because of a duff starter motor. I explained to the Tower that we'd taxy out on three and get the no4 to start on the roll, and if it didn't start we'd taxy back and shut down.This was baffling to the Tower who hadn't got much English and reluctantly agreed it. Fortunately the No4 started and we were airborne (I didn't use the word 'moulins' ) !
Joined: Sep 2010
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From: by the seaside
Reminds me of a story on a 747 in the sand pit who had a similar problem ..engine didn’t start/ relight attempted on take off run which didn’t work/ take off abandoned/ all fuseable plugs blew on the gear/ aircraft stranded whilst a shed load of wheels flown out from LHR. ..(attempt with passengers on board of course).
Some stories you can’t make up.
Some stories you can’t make up.
Joined: Jul 2013
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From: Everett, WA
There was a case at the Portland, Oregon airport - I'm going to say about 20 years ago - biz jet tried to windmill start an engine on the runway and it went very, very wrong (IIRC, the biz jet was a write-off).
BTW, if you're going to do an engine out ferry, SOP should be to pull the ignition and fuel breakers for that engine, especially if you're going to move that engines thrust lever...
There was a pretty notorious case at Boeing Everett maybe 30 years ago. Major operator's chief pilot came out to pick up a brand new 747-400 with Rolls engines. During a ground run, he pulled all four fire handles to shutdown the engines - but then pushed the fire handles back in without setting the fuel condition switches to 'CUTOFF' - re-introduced fuel (and auto-ignition) into a hot turbine as the engines were spooling down. Mother of all tailpipe fires resulted - four of them - along with four melted turbines.
Even through it was the operator's pilot who screwed up (and violated procedures) and toasted the engines (over a million dollars damage each to all four engines), no paperwork had yet been signed so the aircraft still belonged to Boeing - and Boeing had to eat it.
I heard the pilot in question was permanently banned from Boeing property...
BTW, if you're going to do an engine out ferry, SOP should be to pull the ignition and fuel breakers for that engine, especially if you're going to move that engines thrust lever...
There was a pretty notorious case at Boeing Everett maybe 30 years ago. Major operator's chief pilot came out to pick up a brand new 747-400 with Rolls engines. During a ground run, he pulled all four fire handles to shutdown the engines - but then pushed the fire handles back in without setting the fuel condition switches to 'CUTOFF' - re-introduced fuel (and auto-ignition) into a hot turbine as the engines were spooling down. Mother of all tailpipe fires resulted - four of them - along with four melted turbines.
Even through it was the operator's pilot who screwed up (and violated procedures) and toasted the engines (over a million dollars damage each to all four engines), no paperwork had yet been signed so the aircraft still belonged to Boeing - and Boeing had to eat it.
I heard the pilot in question was permanently banned from Boeing property...
Joined: Feb 2002
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From: UK
On the subject of which, I understand to prevent windmilling on the ground on a Tri-Star one day a rubber chock was inserted.
This solution worked quite well until, alas, the ground run was required. The mighty 211 had no problem shredding the chock.
One engine change later....
This solution worked quite well until, alas, the ground run was required. The mighty 211 had no problem shredding the chock.
One engine change later....
Metal bar through the middle of the chock made a mess. 😁
