Steve Franklin wrote:
I have just been watching 'Executive Decision' on TV and the aircraft was a
Boeing 747. The handle for the landing gear seemed very long and it had a
wheel on the end that look a lot like a roller-blade wheel.

So you are saying the wheel has no function other than to provide an instant
identification to the pilot that it's the gear handle?

You're correct, it's so you can tell by feel and visual shape.

power = cylindrical
supercharger = cylindrical with triangular teeth
rpm = ridges like a section of a mechanical gear, flat ridges
mixture = like rpm, but thin sharp ridges
flags = flat with thin edge facing you
heat/alternate air = square facing you
gear = wheel

Kev