Aircraft V-speeds

What V-speeds represent

V-speeds are published reference or limiting airspeeds. The letter codes have common meanings, but the number attached to a code belongs to a particular aircraft and its documented conditions. Model, variant, serial range, weight, configuration, and operating procedure can all matter.

This reference summarizes common fixed-wing terms. It is not a universal numeric speed table, and it is not exhaustive. Many common speeds are published in KIAS, but check the units and conditions in the aircraft documentation. A familiar code does not make a value interchangeable between aircraft.

Common V-speed definitions

Takeoff and climb

• VR, rotation speed. The speed associated with beginning the takeoff rotation, as specified by the aircraft procedure.
• VX, best angle-of-climb speed. It corresponds to the greatest altitude gain over horizontal distance under the stated conditions.
• VY, best rate-of-climb speed. It corresponds to the greatest altitude gain per unit of time under the stated conditions.
• VYSE, best rate-of-climb speed with one engine inoperative in an applicable multiengine aircraft. Use the aircraft-specific procedure and conditions.

Stall and landing configuration

• VS1, stalling speed or minimum steady flight speed in a specified configuration. Read the configuration definition in the applicable manual.
• VSO, stalling speed or minimum steady flight speed in the landing configuration.

Structure and configuration limits

• VA, design maneuvering speed. It is aircraft-specific and may vary with weight. It does not protect against every gust or repeated control input.
• VFE, maximum speed for operating with flaps extended, as defined for the aircraft.
• VLE, maximum speed at which the aircraft may be flown with the landing gear extended.
• VLO, maximum speed for extending or retracting the landing gear.
• VNE, never-exceed speed. Do not exceed the aircraft's published limit.
• VNO, maximum structural cruising speed. The aircraft documents explain the operating range and any related restrictions.
• VMC, minimum control speed with the critical engine inoperative under specified conditions. The value and its context are aircraft-specific.
• VREF, landing reference speed used in an aircraft's approach or landing procedure. Consult the applicable manual for how it is established and used.

Not every code has a standalone glossary page yet. The definitions above summarize common usage, while the aircraft's approved documentation controls the exact meaning and applicable value.

Differences pilots commonly check

VX and VY describe different climb goals. VX is associated with altitude gained per horizontal distance, while VY is associated with altitude gained per unit of time. The speed and procedure for either goal come from the applicable aircraft manual.

VS1 and VSO refer to different configurations. A value for one configuration should not be treated as the value for another. Check the configuration, weight basis, and units that accompany each published figure.

VLE and VLO are also distinct. VLE applies to flight with the gear extended. VLO applies to landing gear operation, which can have separate extension and retraction limits.

VA is not a general-purpose turbulence guarantee. The applicable value can depend on weight, and the design assumptions do not make multiple or abrupt control inputs risk-free. Follow the POH or AFM guidance for the particular aircraft.

For multiengine aircraft, VYSE and VMC answer different questions. VYSE is a climb reference for the stated one-engine-inoperative condition. VMC describes a minimum control speed under specified conditions. Neither code supplies a universal numeric value or replaces the aircraft's engine-out procedure.

Finding an aircraft-specific value

Start with the aircraft make, model, variant, and serial range, then confirm that the POH or AFM revision applies to that airplane. Find the speed in the limitations, normal procedures, or performance section as appropriate. Read nearby notes for weight, configuration, altitude, engine status, and other conditions. Check the aircraft placards and current records as well.

The aircraft reference database includes model pages with source-labeled speed schedules. Examples include the Cessna 172S, Piper PA-28-181 Archer III, and Piper PA-44 Seminole. Each page names the document basis for its data. A profile for one model or revision does not establish the value for another aircraft.

If a source does not publish a value, do not infer it from a similar aircraft. Values from a training website, a cockpit memory aid, or another model's handbook are not substitutes for the approved document that applies to the airplane.

Sources and limitations

General definitions follow common FAA handbook usage. The FAA Pilot's Handbook of Aeronautical Knowledge provides general aircraft performance context. Aircraft-specific values and limitations must be checked against the applicable POH or AFM and placards.

For training and reference only. Do not use this general reference to determine an aircraft operating speed. Verify aircraft data, limitations, procedures, and current conditions against the applicable POH or AFM.