Title: Describe V-speeds.
Course: Aircraft Pilot Training I (20053-I) > Section: Examining Aircraft Instruments, Components, Systems, and Performance

Description should include the following:

- V_S0 (velocity stall 0)—the calibrated power-off stalling speed or the minimum steady flight speed at which the aircraft is controllable in the landing configuration
- V_S1 (velocity stall 1)—the calibrated power-off stalling speed or the minimum steady flight speed at which the aircraft is controllable in a specified configuration
- V_Y (best rate of climb)—the speed at which the aircraft obtains the maximum increase in altitude per unit of time; this best ROC speed normally decreases slightly with altitude.
- V_X (best angle of climb)—the speed at which the aircraft obtains the highest altitude in a given horizontal distance; this best AOC speed normally increases slightly with altitude.
- V_LE (velocity with landing gear extended)—the maximum speed at which the aircraft can be safely flown with the landing gear extended; this is a problem involving stability and controllability.
- V_LO (velocity for landing gear operation)—the maximum speed at which the landing gear can be safely extended or retracted; this is a problem involving the air loads imposed on the operating mechanism during extension or retraction of the gear.
- V_FE (velocity with flaps extended)—the highest speed permissible with the wing flaps in a prescribed extended position; this is because of the air loads imposed on the structure of the flaps.
- V_A (velocity of acceleration—the calibrated design maneuvering airspeed; this is the maximum speed at which the limit load can be imposed (either by gusts or full deflection of the control surfaces) without causing structural damage.
- V_NO (velocity of normal operations)—the maximum speed for normal operation or the maximum structural cruising speed; this is the speed at which exceeding the limit load factor may cause permanent deformation of the aircraft structure.
- V_NE (velocity to never exceed)—the speed that should never be exceeded; if flight is attempted above this speed, structural damage or structural failure may result.

PLT035