Gyroscopic Precession

[FlyGuy78]

Any tips or suggestions with explaining gyroscopic precession?

Thanks in advance...

 

[WrightAvia]

This website helped me immensely...

http://physics.nad.ru/Physics/English/gyro_txt.htm

 

[flywithastick]

Any tips or suggestions with explaining gyroscopic precession?

Thanks in advance...

I guess this fits into the suggestion part of your post. When teaching flying students, I never get beyond the bottom line effect of gyroscopic precession on an aircraft. I've always just explained how it manifests itself, and how to deal with it while flying. If someone want's more, I bet I could come up with some reference matl (link above is pretty good) and a decent explaination, but have never been asked for this.

apply a force (along it's axis of rotation, outside it's center of mass) to a spinning object and the result will be a force out in same direction, with 90° lag (with the rotation). (Attempting to) tilt a rotating mass off its spinning axis is essentially the same as applying a force to some point outside the center of rotation.

I'd use a demonstration device in addition to a verbal description. A small bicycle wheel works really well. Hold one end of the axle with the wheel hanging below, horizontally. Spin it up. After spinning it up a bit, grab the lower axle end with your free hand and tilt it off vertical. You can easily feel the precession.

 

[profile]

People make it too complicated.

Instead of looking at a wheel, imagine just an object attached by a cord that is spinning around. Lets imagine it from a top view, looking down on the the axis of rotation, like we're hovering above someone with one of those tethered airplanes. We'll assume the object is moving in a clockwise direction from our vantage point.

Now, imagine that the object were hit from above as it went through the 9 o'clock position. It now is moving still forward (in the circle) but also downward. It continues to move down until it reaches the 12 o'clock position, but now, because it is still tethered to the same spot, it is pulled upward by the cord it is attached to. As you may now see, the entire arc of rotation has been altered to tilt downward at a point that is 90 degrees to where we applied the initial force.

The only difference between the single point object and a disc is that you need to consider the disc as an infinite number of single points. The net result is the same, for the same reason.

 

[cheater1239]

in the latest issue of "aopa flight training" magazine (sept) there is an article on the subject.