pilot and observer. Slower than pursuit
planes, but more heavily armed.

O.D. Olive drab; color of uniform.

Old Man Captain, Major or Colonel. Usually
applied to commander of the Units.

Panels White muslin, cut into various shapes,
to designate positions of various
headquarters, such as Regiment, Brigade,
etc. When spread on the ground, pilots
could see them and report positions. It
was extremely difficult to get ground
units to display them, since enemy
planes, seeing them, could give location
to their artillery.

P.C. Post of Command. Applied to any
headquarters company on up.

_Poilu_ French private soldier.

Prop Propeller.

Pursuit pilot Pilot of combat plane.

Put the wind up To frighten; to cause to lose courage or
morale.

Revving To accelerate motor rapidly.

Ring sights Type of sight designed to make it
possible to get on a rapidly moving
target. Much time was spent in training
pilots in gunnery and proper
understanding of ring sights.

R.F.C. British Royal Flying Corps.

Saw bones Army surgeon.

Sent west,
Going west To be killed, to die.

Side slipping To slip off the wing.

Solo First flight student pilot makes alone.

Spandau German machine guns used on combat
planes. Twin guns, frequently, with
single control.

Stall To climb so rapidly as to stall the
motor, putting upon it a load heavier
than it can continue to pull. If care is
not taken to ease off, plane will go
into a spin.

Tarmac The line of departure on the field.
Often applied to the entire field.

Toot sweet _Tout de suite_--French phrase, adopted
by Americans. Quickly, hurry up, at once.

Tri-plane German planes, especially Fokker, had
short fin-like projections under the
usua