The pilot of a Gippsland Aeronautics GA 200 agricultural aircraft was conducting topdressing of paddocks and was operating from a nearby forestry airstrip. The pilot had completed the first load with a reduced hopper capacity to assess the aircraft's performance. He determined that sufficient margin existed to increase the next load, and an additional 150 - 200 kg of superphosphate was added to the hopper for the second flight.
The pilot reports that the initial take-off roll appeared satisfactory, with the aircraft accelerating normally. However, shortly after lift-off, the engine coughed momentarily and the aircraft began to lose climb performance. The engine quickly recovered, but not before the climb gradient had been substantially reduced. The pilot had commenced dumping the load but was unable to clear the pine trees upwind of the agricultural strip.
The aircraft entered the trees wings level in the climbing attitude. The aircraft came to rest in an inverted attitude and was substantially damaged during the impact sequence. The cockpit structure survived the impact and the pilot was able to vacate the aircraft without assistance. Subsequent investigation by the aircraft operator did not establish a reason for the reported engine malfunction.