decision speed, up to which it should be possible to abort a take-off and stop safely within the remaining runway length. After reaching V1 the take-off must be continued.
the first of the operational German "weapons of vengeance", or Vergeltungswaffen, the V1 was a pilotless, pioneering cruise missile powered by a pulse-jet engine and carried an 850 kg (1875 lb) high-explosive warhead. They had a range of up to 200 km. Nicknamed "buzz bombs" by Allied troops ("doodlebug" by Australians) due to the sound they made.
(See primary visual cortex)
(Aviation abbreviations:) decision speed (committed to take-off)
Vossy1