fourth and fifth speed gear synchronizer

synchronizer

4GW (fourth-generation warfare)

direct fourth

fifth wheel (FW)

fifth columnist

fifth column

fifth echelon maintenance

supersonic speed (exceeds speed of sound / Mach 1)

variable-speed with speed control

instantaneous vertical speed indicator / instantaneous vertical-speed indicator (IVSI)

Nr gauge (Nr = speed of rotation) / rotor speed sensor

Motor PWM speed separated from PID speed

gear speed decreaser

idler direct speed gear

direct speed gear

landing gear placard speed

third-speed gear

camshaft gear (timing gear)

gear reduction unit / gear-reduction unit

observation and fields of fire, avenues of approach, key and decisive terrain,obstacles, and cover and concealment (OAKOC)

course and speed calculator

wind speed and direction

hovering and low-speed indicator

fuselage and landing gear clearance zone

usage factor for personal clothing, gear and equipment

apparent speed

average speed

blade speed

convoy speed

critical speed

cross-country speed

endurance speed