Engine limit surge stall 737 sim

[Olendirk]

Guys,

is the behaviour of the sim 737 with the limit surge stall realistic? what are the best ways to recover? theres thrust on the stalling engine right? so no rudder action or?


thanks for help!

OD

[Centaurus]

It may depend on the vintage of the simulator? With the 1985 737-300 simulator the compressor stall (or equivalent terminology) is virtually unnoticeable - just a few little thumps which you can barely hear and no discernable loss of power. In short a non-event. Turbine seizure - now that is really noticeable.

[lomapaseo]

is the behaviour of the sim 737 with the limit surge stall realistic

The answer is no for the original software sims.

But I'm not sure of the context of your question. If you are trying to get through a sim ride then I suppose you can always prepare yourself for the actual software experience in that sim. If you on the other hand are trying to prepare for a real life scenario than you should be aware of the differences between what the software/Sim hardware can deliver and what really happens.

In the original Sim configurations both the engine surge characteristics as well as the engine seizure characteristics were well off the mark of reality. With the simulated surge being benign compared to real events and the seizure being too severe. All this should have been updated in later training syllabus to follow the recomendations in this link.

http://fromtheflightdeck.com/Stories/turbofan/

[mrjet]

is the behaviour of the sim 737 with the limit surge stall realistic?

Don't know, never experienced it in real life

what are the best ways to recover?

Do the recall items, disconnect A/T and reduce thrust until surge/stall stops or until T/L is closed. Then do the non-normal checklist.

theres thrust on the stalling engine right? so no rudder action or?

On CAEs 737NG simulators there are 2 different stalls/surges, recoverable and unrecoverable. Either way initially the engine will produce thrust while it's recovering from the surge, then it'll lose thrust again, recover etc. If it happens during takeoff there will be a great thrust assymetry and you will need to use rudder but you will have to ease out on the rudder when the engine recovers. There will be alot of rudder action until the engine recovers or the thrust is reduced to idle or engine is shut down.

If recall items are not done the engine will continue to surge and EGT will go above limits.

[barit1]

The sound of a stall is quite an explosion - no mistaking it! :eek:

If the engine keeps turning, then it's still making thrust - little or no yaw. If it quits turning, then it's OEI.

[lomapaseo]

The surge cycle on these engines is much faster than the rotor inertia can follow. So the thrust loss pretty much follows the noise. For each bang figure on the thrust dropping about 50% of where it started from in about a half second. This will give you a hell of a kick and spill your coffee at high power.

If the blades are mostly there (albeit maybe damaged) the thrust will recover to about 90% of where you started in about 1.5 sec, hurling your coffee in the other direction. For takeoff events you should be able to clear obstacles even if both engines surge and recover between V1 and V2. The real workload is doing the tap dance on the rudder pedals and of course the clean up afterwards.

The rotor seizure that I have experienced during takeoff in the sims is docile in that it only yaws in one direction and is far less confusing to the senses.

caution: not all sims are programed by the same software

[Clarence Oveur]

Engine limit surge stallThat sounds like the name of a checklist.

As has been alluded to in previous posts, engine failure characteristics in most simulators bears little resemblance to actual engine behaviour. At the same time most engine malfunctions during simulator passes are introduced, and understood by the crew, for the purpose of engine out exercises.

There is evidence to suggest that there is widespread poor understanding of engine behaviour, as data collected by Airbus shows that the majority of IFSD were unnecessary. This is perhaps induced by an unintentional shut-down conditioning being introduced by simulator syllabuses.

[Ashling]

The engine limit surge stall covers more than just a surge or compressor stall. It may well be a runaway or limit exceedance you are dealing with.

[lomapaseo]

The engine limit surge stall covers more than just a surge or compressor stall. It may well be a runaway or limit exceedance you are dealing with.

Agree, so we may be only guessing what the original poster meant to ask. But threads like this have a way of meandering on :)

[Olendirk]

yes,im talking about a surge, sorry for that!