It's there on all jets I've flown.
Mode7
Originally Posted by Rainboe View Post
'so that debris is not thrown around inside the undercarriage bay.'
Erm.... not quite. Each wheel on the 747 weighs 160kgs. So 16 wheels weighing 160kgs doing 180knots is a serious gyroscopic force - 2.56 tonnes of gyro (half that actually as it is only the wing gear that retracts sideways, body and nose retract forward along the direction of gyro rotation)
If you disagree with my statement, perhaps you could explain why the 747 body gear (which retracts in a fore/aft plane) also automatically brakes during the retraction sequence? Your last sentence doesn't follow your initial line. You only have to look inside the nose bay to see how much debris gets thrown around.