Work—Force X displacement.
Wind-Screen—A small transparent screen mounted in front of the pilot to protect his face from the air pressure.
FOOTNOTES:]
1 ([return])
[ Propeller Slip: As the propeller screws through the air, the latter to a certain extent gives back to the thrust of the propellor blades, just as the shingle on the beach slips back as you ascend it. Such “give-back” is known as “slip,” and anyone behind the propellor will feel the slip as a strong draught of air.]
2 ([return])
[ Helicopter. An air-screw revolving upon a vertical axis. If driven with sufficient power, it will lift vertically, but having regard to the mechanical difficulties of such construction, it is a most inefficient way of securing lift compared with the arrangement of an inclined surface driven by a propeller revolving about a horizontal axis.]
3 ([return])
[ Pancakes: Pilot's slang for stalling an aeroplane and dropping like a pancake.]