Learn what V1, VR and V2 mean during take-off, why they change for every flight, and when pilots reject, rotate or continue after engine failure.
V1 is the take-off decision speed: the first action to reject must begin no later than V1. VR is the speed at which the pilot starts raising the nose. V2 is the take-off safety speed used to ensure the required initial climb performance if one engine fails.
In real-world aviation, these labels are associated mainly with multi-engine transport-aircraft performance planning. They are calculated references, not universal speeds, and are normally presented as indicated airspeeds on flight-deck displays, speed bugs or take-off data.
What is the difference between V1, VR and V2?
The three speeds mark separate decision, rotation and climb-performance points during the take-off.
| Speed | Meaning | What happens |
|---|---|---|
| V1 | Take-off decision speed | The crew must initiate a rejected take-off no later than V1. After passing it, the normal response to failures covered by the performance calculation is to continue. |
| VR | Rotation speed | The pilot applies the planned nose-up input. The aircraft usually lifts off shortly afterwards, rather than precisely at VR. |
| V2 | Take-off safety speed | The aircraft must achieve the required safety speed by the certification-defined point and meet the specified climb performance with an engine inoperative. |
VR is not a pitch angle, and V2 is neither the lift-off speed nor the flap-retraction speed. Other references such as VMC, VREF and VX cover different phases; our wider explanation of aviation V-speeds sets those terms in context.
Does V1 mean the aircraft must take off no matter what?
No. V1 is a performance and procedural boundary, not a physical point beyond which stopping is impossible.
Before V1, crews reject for conditions defined by their approved procedures. At or after V1, continuing is normally safer for an engine failure or another fault covered by the take-off calculation, because a late rejected take-off may exceed the available stopping distance. A failure that leaves the aircraft incapable of safe flight is a different situation and requires the crew to use the applicable emergency procedure.
Calling V1 “the engine-failure speed” is technically wrong. Performance calculations assume the engine fails at an earlier reference called VEF, allowing for recognition and reaction before the first stopping action at V1.
Are V1, VR and V2 the same on every flight?
No. V1, VR and V2 are calculated for the aircraft, runway and conditions of that particular departure.
- Aircraft take-off weight and centre of gravity
- Flap or slat configuration and thrust setting
- Runway length, slope and surface condition
- Wind, temperature and pressure altitude
- Obstacles and required climb performance
- Aircraft-system penalties such as anti-ice or bleed-air use, where applicable
The speeds do not always move together. V1 is particularly sensitive to runway and stopping performance, while VR and V2 are strongly tied to weight, configuration and controllability requirements. V1 must not exceed VR, although the two may legitimately be equal.
A mistake we see constantly in simulation is copying a published set of numbers into a different departure. A worked Airbus A320 example of flight-specific V-speeds shows why even the same aircraft type can receive different values from one take-off to the next.
How should V1, VR and V2 be used in a flight simulator?
Use the simulated aircraft’s own performance calculator, electronic flight bag, flight-management system or documented performance tables whenever available.
- Calculate the speeds: enter the correct weight, runway, weather, thrust and flap data rather than using generic internet figures.
- Cross-check the result: confirm that V1 does not exceed VR and that V2 is plausible for the aircraft and configuration. Equal V1 and VR values are not automatically an error.
- Use indicated airspeed: do not substitute ground speed or manually add and subtract the headwind component. The performance calculation already accounts for wind where required.
- Rotate at VR: apply a smooth pitch input and follow the aircraft’s take-off guidance. Do not wait until V2 to raise the nose.
If the aircraft reaches VR but refuses to lift off, the likely causes are loading, trim, flap configuration, control calibration or an incorrect rotation technique rather than the definition of VR itself. Our rotation and take-off troubleshooting checklist for flight simulators covers those faults directly.