Gyroscopic effect of engine fans

[airstairs]

Curious to know if the gyroscopic effect of rotating components in engines has a major effect on heavy aircraft handling. How does the 777 handle at various engine rotational speeds....given the monster sized fans on them ?

[747FOCAL]

It's all taken into account, but the gyroscopic load is not much in the big picture. The engines are also canted a bit to help as well.

[PAXboy]

If I recall correctly, some of the early large props were set to rotate in opposite directions, to counteract the pull?

I would presume that designing a jet engine to be a mirror image and turn in the opposite direction would be an horrendous expense. No one wants to have only 'left hand' engines, when a right hand is needed!

With props, only the gears needed to be reversed?

[Pielander]

Rolls engines turn clockwise as viewed from the front, while GE & Pratts turn anticlockwise, so you could have one of each, couldn't you?! :D


(Oh, hang on... that's a stupid idea! :p)

:) :) :)

[PAXboy]

Pielander - that is a Pratt of an idea and I hope that your mind Rolls onto a better one soon. In General, we need more Electric thoughts. ;)

[spannerhead]

The gyroscopic effect of the centre engine of the B727 is quite pronounced because it is horizontally and vertically in line with the fuselage. Whilst rigging the spoiler actuators, the left hand spoilers are rigged to actuate with less aileron input than the right hand spoilers. This is because it is inherently easier for the 727 to turn right due to the gyroscopic effect of the centre engine. This is most pronounced during a power off test flight when A and B spoilers are switched off and roll control is purely from the ailerons. I have had captains query this in the past during test flights saying that it requires more effort to turn left.
I get him to back No2 to prove it. :cool: