In today’s article, we will talk about one of the most wonderful moments in aviation. Lean back, fasten your seatbelts, taxi to the runway, and enjoy your view while we take off!
Have you ever asked yourself, how does a pilot know when to pull the yoke? Or how does he know whether to continue the takeoff or stop immediately in case of an engine failure? The V-Speed is the key!
V1 – The Decision Speed
In case of an emergency during the takeoff procedure, the pilots need to take action by using the brakes, spoilers and if needed the reverse thrust before reaching the V1 speed.
If the airplane reaches the V1 speed, the pilots would continue the takeoff either way. A failure of one engine is not a problem at all to takeoff for modern aircraft and therefore safer than aborting the takeoff procedure. The reason is that the length of the runway might not be long enough to be able to fully stop the plane. Only one wing left? Stop the aircraft no matter which speed, of course.
Vr – The Rotation Speed
Pilots hear a callout „Rotate!“. What do they have to do now? That one is easy. As soon as the aircraft reaches the Rotation Speed, the yoke or the sidestick is being pulled back gently to lift the nose of the bird. Pulling the yoke or sidestick too abruptly could result in a tailstrike.
V2 – The takeoff safety speed
This is the minimum speed for an aircraft to safely climb even if one engine fails. This speed is to be maintained until the Acceleration Altitude is reached.
The Acceleration Altitude is the altitude above ground level between 1‘000 and 1‘500 feet. If arrived, the pilots reduce the thrust and the aircraft’s pitch to accelerate to a safe speed to raise the flaps and slats. As soon as the aircraft is in clean configuration, the pilots can reach their desired climb speed and altitude.
The calculation of the V-Speeds is very complex and includes so many factors like the aircraft’s weight, length of the runway, weather and runway conditions etc. However, it is very important to calculate them carefully and correctly. A mistake could result in a too early rotation, which in turn could be the trigger of a possible stall.