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a350pilots
11th Mar 2019, 13:36
Hi everyone,

After actioning QRH gravity extension checklist due to an abnormal L/GEAR indication, is the gear still retractable
(provided G HYD is available)?

YES/NO?

Reasons why it should not be attempted?
What are your thoughts?

QRH suggest NOT to reset it, but except in training flight, so that gear door closed and NWS is available.
FCOM also suggest a reset in flight.

Does that mean the LGEAR can be retracted?
I thought it was always a one way street.

UberPilot
11th Mar 2019, 16:25
Had this scerio in the sim recently. In the sim at least, if you reset the gravity extension handle and have G Hyd power available then the gear will retract.

The context was a scenario where the nose gear doens't down-lock (including after recycling) into a short runway where the length is insufficient to land after applying the landing with abnormal gear checklist. So in this case, the ECAM will ask for gravity gear extn. If you still fail to get 1 green triangle on each wheel then you can reset the handle, raise the gear and then divert clean.

screwdriver
11th Mar 2019, 17:21
The QRH procedure used to include a reset procedure. Yes, if you reverse the procedure and have the G Hyd available then the gear will retract.

a350pilots
11th Mar 2019, 17:59
Thank you guys.

MSN001
12th Mar 2019, 09:45
When the ECAM instructs you to recycle the L/G, does this mean a full mechanical movement of the gear assembly or just a flip of the gear lever to change LGCIU? How much time does a “correct” gear recycle take?

cinocav
12th Mar 2019, 14:12
REF: FCOM PRO ABN L/G NOT DOWNLOCKED

To recycle the landing gear, the flight crew must perform the following actions:

Move the landing gear lever up
Wait for the landing gear to uplock and for the landing gear doors to close.
Simultaneously monitor the WHEEL page on the System Display (SD)
Move the landing gear lever down.


The active LGCIU changes when the landing gear is recycled.

OPEN DES
13th Mar 2019, 04:56
Yes, it is reversible. I have seen a few (incl the reset) during test flights. During tests there is actually a small delay included after every turn on the handcrank to avoid damage to the doors, this is not an issue in actual abnormal/emergency operation where risk is assessed differently. (In the old days the delay was actually mandated by OEB, not anymore)
Toptip: stow the handcrank after grav extension. This ensures that the gear remains locked under all circumstances. Also this allows for access to the park brk handle, handy for loss of braking for example.....

You most likely have seen your TRI/TRE resetting the handcrank after the exercise. Normally if you can do it in the sim, it will also work in the aircraft.
FYI: The ENG firepushbuttons can be reset as well. It’s an ‘irreversible action’ from a procedural point of view only, however from a technical perspective you can reset them.

a350pilots
14th Mar 2019, 17:04
Great reply. Cheers mate.