Landing Gear, Ice & Rain, Fire Flashcards
(107 cards)
Which hyd system controls the gear?
A
How are nose wheels stopped when retracted?
Snubber pad in wheel well
How are main wheels stopped when retracted?
Normal brakes auto applied
What is the frangible fitting?
If a tyre blows and auto brakes fail to stop the wheel spinning, on retraction the flailing tyre strands will break the frangible strut at the opening of the wheel bay. This will cause an immediate hyd leak stopping retraction of that leg. 2-4 litres of hyd will be lost before the leak is cut off and the gear lowers back down, preventing damage inside the wheel bay
If eng 1 fails on TO how is the gear raised?
LGTU, uses B system hyd to raise the gear
What are the criteria for the LGTU to work?
- Airborne
- no 1 eng fail
- gear handle up
- EITHER main leg not locked up
If hyd A fails how can gear be lowered?
Manual extension handles pulled, lock release, then gravity & aero drop
How is NWS controlled from the flt deck?
Tiller (capt only except a few ac)(+/-78 degs) NWS (+/-7degs)
How is the gear held up?
Mechanical locks, selecting OFF depressurises the hyd
Can you raise the gear handle on the gnd?
No A-G logic prevents it
If the emergency gear lowering handle door (aft of the aft elecs panel on the floor) is open, what does this prevent?
Raising the gear
When is NWS enabled?
Gear handle down and nose leg oleo compressed
Are the alt gear green on the o’head panel just bulb repeaters?
No, separate sensing system
What types of brakes are there, how do you tell?
- Carbon – listed on DS app as CAT-N
- Steel – listed on DS app as CAT-C
How should you brake with carbon brakes?
Long steady applications (life is limited by applications)
How should you brake with steel brakes?
Short small applications (life is limited by temperature)
What indication is there on flt deck that the alternate brakes are being used?
None directly, you may have the associated warnings from a hyd fail. Also auto brake will not arm, but this may be due to a different failure
What 3 braking systems are available?
Normal (hyd B), alternate (hyd A), accumulator (from stored hyd B)
Is anti-skid available with altn or accumulator braking
Yes, but works on pairs of wheels on altn. Reverts to individual wheels with accumulator as it is back through the normal (hyd B) valves
If hyd A fails, can auto brakes be used?
Yes, they only work on normal (hyd B)
Approx how many applications will the brake accumulator give you?
7
How do you know the accumulator is discharged?
Residual 1000psi base nitrogen pressure
If you select auto brake 2 and use REV thrust, how much less distance will you stop in?
None, auto brake assumes no REV or spoilers. If REV and spoilers are available, auto brake is reduced to give the same rollout distance
When do auto brakes come on?
Both TLs at closed and main wheels >60 kts