What do V1, VR, and V2 represent in takeoff data and how are they used?

• A. V1 is the cruise speed, VR is vertical rate, V2 is the maximum takeoff velocity.
• B. V1 is the minimum speed to continue takeoff after engine failure, VR is rotation speed, V2 is the landing speed.
• C. V1 is the decision speed, VR is rotation speed, V2 is the minimum takeoff safety speed.
• D. V1 is the decision speed, VR is rotation speed, and V2 is the minimum takeoff safety speed; they guide the takeoff thrust and rotation.

Answer: (D)

V1, VR, and V2 are the takeoff performance speeds that define how a takeoff is planned and carried out. V1 is the decision speed: it marks the point during the takeoff roll at which you must decide whether to continue or abort. If an engine fail occurs before reaching V1, you can stop on the runway within the available distance; if the failure happens at or after V1, you must continue the takeoff. VR is the rotation speed: when you reach this speed, you begin to raise the nose to liftoff attitude and lift the aircraft off the ground. V2 is the takeoff safety speed: the minimum speed you must be able to reach and maintain in the initial climb with one engine inoperative, ensuring you can meet clue climb gradient and obstacle clearance.

These speeds are determined from the airplane’s weight, runway length and conditions, altitude, temperature, wind, and flap setting, and you’ll see them in the takeoff performance data for the flight. They guide the takeoff profile: the thrust setting (often TOGA) is chosen to achieve the required acceleration to V1, reach VR for liftoff at the proper attitude, and then accelerate to or through V2 to maintain a safe climb, including scenarios with an engine failure.