Is there Time Limitation For A340 & B747 During Windmill???
Hi,
I read that certain aircraft like A340 have limitation of duration (7 or 8 hours) for windmilling engine (after engine shutoff in flight). Since quadjet/trijet are allowed to continue the flight in case of engine shutdown, is there such limitation in other aircraft like B747....? or even for twin during 180 or 207 minutes of diversion.
-Is this limitation due of the viscosity of the oil after being cold soaked during hours of windmill, or due to the lack of oil pressure because the oil pump does not provide the adequate lubrication during windmill?
-If the cause is the lack of adequate oil pressure, can this cause affect especially the N2 shaft bearings (assuming N2 is higher than N1)? OR
N1 shaft bearings? in certain flight conditions during windmill N1 is similar to N1rotation during flight idle (according to certain website)
-The questions mentioned above lead to another question:
What are the engine parameters (N1, N2, oil temperature, and oil pressure) for a stabilized windmilling engine after driftdown? may be it seems difficult to remember windmilling engine parameters during such rare event, but certain pilots are lucky (according to this forum one pilot performed about 30 inflight engine restart). If you cannot remember these parameters, it will be VERY HELPFUL AND NICE if someone can get these parameters from the sim and post these information here (if possible).
Feedback VERY appreciated. Thank you.
Best regards.