Aircraft was 1 of 4 assembled to drop parachutists who were attempting to establish an Australasian record parachute stack. Pilot commenced take-off run and deliberately held the tail down to improve the aircraft's rudder control. After traveling 100 yards the aircraft veered off the runway. Shortly after becoming airborne it crossed a post and wire fence and clipped some toi toi grass on the far side of the fence. Aircraft damaged and occupants injured in attempted forced landing.