Thanks for the explanation, I will try to find you a Boeing AFM or MEL page reference this morning, but note that I did say "This is quite easily proven by the fact that with a brake deactivated or removed, the crew are required to leave the gear down for 2 minutes after takeoff in order for the wheels to stop spinning.
I didn’t know my audience, so I really didn’t want to expand into the differences between deactivating brakes by capping the lines and removing them, or by deactivating the system using a "deactivation" tool.
Using the deactivation tool allows you to do a normal takeoff with some performance adjustments as it uses residual pressure to stop the wheels. Capping/removing leaves the brakes with no residual pressure; therefore you have a 2-minute spin down time, hence the requirement to calculate a gear down departure.
I have NO A330 knowledge, so I will check out if this procedure applies to the 757, it most certainly does on the 747.
As for the gyroscopic forces, I have browsed through the Boeing Jet Transport Performance Methods manual and can find no reference to these forces during takeoff or climb. Panman, could you please point me towards a technical reference, which states that, they are a factor. Thanks,