At the time of the accident, sport parachute jumping was taking place at Gryttjom airfield, Sweden. The pilot, who was involved in these operations, intended to take off with 21 parachutists on board the aircraft for them to carry out a normal jump near to the airfield. After the pilot had carried out the normal pre-flight checks the parachutists boarded the aircraft and the pilot began to taxi the aircraft towards the beginning of the runway for a takeoff from runway 36. He did not notice anything abnormal, neither during the preparations for takeoff nor during the initial taxiing. After taxiing for a few minutes at low speed, suddenly the right main landing gear broke, whereupon the aircraft tipped over to the right and the right wing struck the ground. The aircraft then slowed down, turned somewhat to the right, and stopped. The pilot ordered an emergency evacuation and those on boards unclipped themselves and quickly exited the aircraft via the normal parachuting door. At about the same time the pilot switched off the engines, turned off the main fuel cocks and main circuit breaker, and exited the aircraft himself. Once outside the aircraft the pilot checked that everyone else had exited the aircraft and moved to a safe location. CAUSES OF THE ACCIDENT: “The accident was caused by fatigue cracking in the right main landing gear. A contributory factor was an inadequate maintenance system for this type of aircraft in respect of checking for cracks.”