T-39 FLIGHT PREPARATION
Maximum Operating Speed
Final Approach Speed at threshold (1.3 x Vso)
Stall Speed dirty
Best Angle of Climb
Best Angle of Climb, single engine
Best Rate of Climb
Best Rate of Climb, single engine
Wet Runway, standing water
Zero Fuel Weight
Revolutions Per Minute - measured in percent
(1) V1: The speed above which the takeoff is continued and below which the takeoff is
abandoned in the event of an engine failure.
(2) Refusal Speed: Used in conjunction with critical field length chart to determine
speed at which an aircraft can either accelerate to refusal speed and then stop, or
accelerate to refusal speed and continue takeoff while one engine is failed at refusal
speed. All available remaining runway will be required to get the aircraft airborne.
(3) V2: Must be not less than 1.1 x VMC or 1.2 VS and must be attained before reaching
a height of 35 feet.
(4) VR: The speed at which the aircraft is rotated to the takeoff attitude. VR must not
be less than V1 or less than 1.05 x VMC. It must also be high enough to allow V2 to be
attained before the aircraft reaches a height of 35 feet.
(5) VS: The stalling speed or the minimum steady flight speed at which the aircraft is
(6) VMCA: The speed required to provide sufficient control to fly a straight path over the
ground with a failed engine. This speed is based on the engine windmilling, takeoff
thrust on the good engine, and no more than 5º bank away from the failed engine. At
minimum control speed, it may be necessary to sacrifice altitude for airspeed while
putting the aircraft in clean configuration and obtaining sufficient airspeed to climb.