A330 undercarriage
 

Noticed the last 2 days in a row now, Jetstar A330 taking off from runway
34L in YSSY, left it undercarriage down after tkof. It was still down well after the left hand turn on the SID today.
Is it simply to allow the brakes to cool after a long taxi or is there some other reason for this?
I have seen a Cathay A330 do the same, but he took off on 16R, so not so long a taxi.

have to ask the driver of the bus, but must have been following procedures.:ugh:

If a brake unit has been disabled then it will not despin when the gear is seleceted up. This puts unnecessary strain on the gear due to the centripedal forces on the retract mechanism. To overcome this the MEL asks for the gear to be left extended for XX minutes after T/O to allow the unbraked unit to stop on it's own.

SO what happens on A380 when some of the rear wheels do not even have brakes fitted.

You may notice the body gear on the 380 does not retract through 90 degrees, ergo no force imposed (unless you simultaneously roll right or left 90 degrees during takeoff)

Operating with brake unit u/s or tachometer

MEL entry

42-01 Main Wheel Brakes

Note : If one brake only is inoperative and the AUTO/BRK function is operative and used, a braking asymmetry can be expected at takeoff and landing, and compensated by the pilot using rudder.

Takeoff Performance
The following method may be used for takeoff performance determination if no takeoff data (Predetermined by using OCTOPUS program or other equivalent program with present failure case taken into account) is available.

Note : If both engines are operative, keep landing gear down for two minutes. In case of engine failure at takeoff, retract landing gear when positive climb. Vibrations may be present during one or two minutes after landing gear retraction.