A race competitor has been airlifted to hospital in a critical condition after a crash during a land speed record attempt on remote salt flats in South Australia.

Speed Week competitor Trent Clare from Broken Hill crashed on Tuesday on Lake Gairdner, about 150 kilometres north-west of Port Augusta.

Spectators saw his car roll several times as Clare crashed while trying to break a 200-miles-per-hour (321kph) speed record for his class of car.

Clare was treated at the scene before being airlifted to the Royal Adelaide Hospital.

Police were heading to the salt pans on Wednesday morning to investigate the circumstances of the crash.

Competitors have been at Lake Gairdner since last Friday and say there has been an excellent surface for racing this year.