Engine Seperation
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Joined: Oct 1999
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Engine Seperation
Hi
Bar no hydraulic fluid left, what other indications will you have of engine Seperation?
Learning experience today had lots of 0's and put it down as engine severe damage as all indications were there.
Thank you.
Bar no hydraulic fluid left, what other indications will you have of engine Seperation?
Learning experience today had lots of 0's and put it down as engine severe damage as all indications were there.
Thank you.
Joined: Apr 2008
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From: UK
From SLF
As a matter of interest, is it the case that cabin crew observations do not play a formal role in the procedures pilots use to diagnose problems like this?
I mean, if one of them got on the phone and mentioned that an engine was missing, or that there was burning fuel on the ground underneath an obviously broken engine, presumably the pilots would take them seriously, no matter what the official procedure said...
In the absence of a view from the cockpit and video displays of the wing, a pair of trained eyes down the back of the aircraft could be a useful thing.
So have I touched on the answer to my question - training (and the cost of it)? But for basic things like fire or absence you don't really need much training.
I wouldn't be surprised if retro fitting a video system was also much more expensive than one might casually think. However for new designs it would surely be a piece of cake. Or are they so keen to carry over pilot type ratings that they are adding nothing new like this at all? That would be a pity...
I mean, if one of them got on the phone and mentioned that an engine was missing, or that there was burning fuel on the ground underneath an obviously broken engine, presumably the pilots would take them seriously, no matter what the official procedure said...
In the absence of a view from the cockpit and video displays of the wing, a pair of trained eyes down the back of the aircraft could be a useful thing.
So have I touched on the answer to my question - training (and the cost of it)? But for basic things like fire or absence you don't really need much training.
I wouldn't be surprised if retro fitting a video system was also much more expensive than one might casually think. However for new designs it would surely be a piece of cake. Or are they so keen to carry over pilot type ratings that they are adding nothing new like this at all? That would be a pity...
Joined: Jun 2000
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From: last time I looked I was still here.
I can only comment on what the sim shows; I am curious why your SFI/TRI's can't answer this.
Firstly: you could be flying freight or a ferry, so CA eyes down the back might be unavailable.
2ndly: Yes the same checklist, but I'd be very cautious about deploying LED's with a separated engine. If the runway did not require it I might configure for a non LED landing if there is no option to make a visual inspection of the LED's. It could be night time, or the windows (freight version) could be blanked. Vision from the flight deck is only the 2 outboard LED's.
3rdly: The '0's' in the engine gauges are not the primary indications. The N1% shows 0, but the ancillary gauges show 'blank'. That means the sensor connection is missing. It is also why I suggest to students that during their analysis of the engine instruments, said out loud, is to differentiate between "no oil pressure" & "blank oil pressure". They mean different things and to non-english speaking (primary language) pilots under stress the wrong understanding is possible.
In the FFS sim I used to demonstrate all the different engine failures in sequence to confirm understanding of the possibilities. I was amazed how many students had not seen a surge or separation during FBS phase.
Firstly: you could be flying freight or a ferry, so CA eyes down the back might be unavailable.
2ndly: Yes the same checklist, but I'd be very cautious about deploying LED's with a separated engine. If the runway did not require it I might configure for a non LED landing if there is no option to make a visual inspection of the LED's. It could be night time, or the windows (freight version) could be blanked. Vision from the flight deck is only the 2 outboard LED's.
3rdly: The '0's' in the engine gauges are not the primary indications. The N1% shows 0, but the ancillary gauges show 'blank'. That means the sensor connection is missing. It is also why I suggest to students that during their analysis of the engine instruments, said out loud, is to differentiate between "no oil pressure" & "blank oil pressure". They mean different things and to non-english speaking (primary language) pilots under stress the wrong understanding is possible.
In the FFS sim I used to demonstrate all the different engine failures in sequence to confirm understanding of the possibilities. I was amazed how many students had not seen a surge or separation during FBS phase.
Thread Starter
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Thanks.
Can you explain more about note 2 please?
I had all indications there just lots of 0's. I always thought that these would not be there at all in a Seperation. Hence why I called it severe damage.
Thank you
Can you explain more about note 2 please?
I had all indications there just lots of 0's. I always thought that these would not be there at all in a Seperation. Hence why I called it severe damage.
Thank you
Joined: Jul 2013
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From: Everett, WA
FADEC supplied parameters would 'blank', while analog inputs would read "0" (note that your rotor speeds use the FADEC as the primary source, but have analog backup).
But a dead FADEC would also result in blank parameters.
But a dead FADEC would also result in blank parameters.
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From: last time I looked I was still here.
Note 2. Ref: DC-10 Chicago: B747 Amsterdam. Both had engine separation problems and both, unbeknown, had LED damage. DC-10 had engine failure on takeoff and reduced speed to V2 and stalled the damaged wing. B747 deployed LED's for landing and stalled the damaged wing. No doubt there has been others, but little thinking outside the box can help.
Joined: Mar 2002
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From: Florida
Note 2. Ref: DC-10 Chicago: B747 Amsterdam. Both had engine separation problems and both, unbeknown, had LED damage. DC-10 had engine failure on takeoff and reduced speed to V2 and stalled the damaged wing. B747 deployed LED's for landing and stalled the damaged wing. No doubt there has been others, but little thinking outside the box can help.
Engines that don't fail but just separate do different things to the aircraft whilst departing.
Side load departures in turbulence or spin may also vary.
Yet keeping the briefing simple and recallable in training serves a value so I wouldn't want to mess with that at this time.
Joined: Jul 2013
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From: Everett, WA
I don't have first hand knowledge of the 737, but standard Boeing design practice is to blank displays if the digital data is lost or invalid. With analog signals, you can't tell the difference between lost and valid but zero, so they will still display zero.
Next time you do an engine start, before you do anything look at the engine displays - digital inputs only from the FADEC will be blank until the FADEC is powered, anything that is analog (or has an analog backup - rotor speeds) will read zero. That's pretty much what you'll see if the engine decides to go it's own way
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From: Australia
Regarding those instruments with analog backup, e.g. N1/N2 on the 737NG. The analog signal is fed to the DEUs directly. Would the DEU be smart enough to recognise a missing N1/N2 sensors as a failure rather than zero rpms (and therefore show blank indications)?
The N1/N2 and accelerometor sensors also feed directly into the Airborne Vibration Monitoring Unit (AVM). I wonder how this reacts to open circuit sensors?
How catastropic is catastrophic? Both rotors locked? EEC power wiring destroyed? EGT harnesses damaged? Engine oil tank ruptured? Engine oil quantity wiring damaged?
Engine oil tank quantity goes directly to the DEUs. Again, is the DEU smart enough to recognise open circuit wiring Vs empty tank (and show blank for open circuit wiring)?
Perhaps we could have some Maintenance Engineer input here? With the cannon plug removed from an oil quantity sensor, what are the cockpit indications? The Maintenance Manual and FIM don't seem to offer any clues.
The N1/N2 and accelerometor sensors also feed directly into the Airborne Vibration Monitoring Unit (AVM). I wonder how this reacts to open circuit sensors?
How catastropic is catastrophic? Both rotors locked? EEC power wiring destroyed? EGT harnesses damaged? Engine oil tank ruptured? Engine oil quantity wiring damaged?
Engine oil tank quantity goes directly to the DEUs. Again, is the DEU smart enough to recognise open circuit wiring Vs empty tank (and show blank for open circuit wiring)?
Perhaps we could have some Maintenance Engineer input here? With the cannon plug removed from an oil quantity sensor, what are the cockpit indications? The Maintenance Manual and FIM don't seem to offer any clues.