Come on, Regiment - give us at least a sporting chance to help you, mate.
It could be one of numerous problems, but you've given us precisely no information about the ESC, radio, type of battery, motor, prop, is this first-time out with the model etc etc.
Wombat does theory; I do soldering and b*sh*t; Stallspeed can recite Farnell's entire catalogue from memory, and PMK has left the building. None of us, however, can do telepathy.
Ball is back in your court.
FLJ