Engine Seperation

[Pin Head]

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.

[lomapaseo]

If this is a question about simulator training

then its a book answer

if its a real life question then the answer will vary with other factors

[grounded27]

Screaming PAX?

[Pin Head]

Book answer then please.

[PDR1]

Letters from the engine's lawyer demanding vacant possession of the aircraft's hangar and 50% of its future revenue, plus another 10% for each of the three APUs...

PDR

[RAT 5]

Type A/C please.

[Pin Head]

B737ng
Thank you

[Intruder]

Look out the window?

[felixthecat]

Isn't the memory item 'Engine Severe Damage and Separation' ? So its the same checklist anyway....
(Been a long time since I was on the 737 so could well be wrong)

[msbbarratt]

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...

[RAT 5]

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.

[Pin Head]

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

[tdracer]

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.

[RAT 5]

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.

[lomapaseo]

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.

several early B737s with JT8D and B727s, and B707s. No wing damage (different aero forces on released engine) +Kalita B747

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.

[Pin Head]

So at 'Identify failure' how many of you check systems page as well as primary and secondary engine data?

[Pin Head]

So just to confirm physically no information missing?
I.e just black?
I think the 756 would do this on a seperation.

[B737900er]

If the indications all read zero I would expect at separation. if the N1 and N2 read zero and possible high EGT I would diagnose that as an Turbin Seizure so, Engine fire, severe damage, separation NNC.

[Pin Head]

Thanks.
But do any indications just dissapear? So black background only,

[tdracer]

Thanks.
But do any indications just dissapear? So black background only,


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 :E

[NSEU]

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.

[de facto]

I was taught told since day one,if both N1/N2 are down to a 0, all other parameters(oil/FF) inop AND fire det FAULT is illuminated then to treat it as separation.
Now,the severe damage and separatin are in the same checklist and require the same memory items.
Never hurt anyone to check with the cabin and get a photo shot of it;-)

[de facto]

EEC power wiring destroyed?You mean the whole EEC would be gone now, wouldnt it?:p

[lomapaseo]

Never hurt anyone to check with the cabin and get a photo shot of it;-)

Pan Am had one back in the 90's where it really did seize just after rotation. They cleaned up the aircraft and made an uneventful ATB

The third guy in the cockpit went back to take a look over a womans shoulder and related that he saw a big gaping hole in the aft section of the engine. The woman remarked that she saw flame out of the engine and was concerned. He told her it was nothing to worry about an went back to the cockpit and said to the pilot wholly ch***t there' a whopping hole in the side of that engine you can fit your head in!!

I heard this from the guy himself who flew the next day's aircraft back to JFK

[NSEU]

EEC power wiring destroyed?

You mean the whole EEC would be gone now, wouldnt it?



I thought we were trying to distinguish between catastrophic engine failure and separation? Catastrophic might include total destruction of EEC wiring which would, in some ways, mimic separation.