Shortly after takeoff, at a height of about 250 feet above the ground, the engine lost power. The pilot applied carburettor heat which he said resulted in a brief surge of power after which all power was lost. The pilot dumped the load but while he was manoeuvring to avoid a fence the aircraft stalled and hit the ground heavily. Subsequent investigation revealed that the engine fuel system was contaminated with water. The pilot had refuelled the aircraft from a 200 litre drum prior to takeoff. Although he checked the drum for water contamination prior to refuelling and then completed a fuel drain check of the aircraft fuel tanks, he did not detect water. Further investigation revealed that the 200 litre drum from which he refuelled had been sitting in a utility in heavy rain for a number of days and the drum bung had a faulty seal. The pilot believed there was no doubt that he had pumped water contaminated fuel into the aircraft fuel tanks which then found its way into the engine. Factors The following factors were considered relevant to the development of the accident: The pilot did not detect water in the fuel when he checked the drum source prior to refuelling the aircraft tanks. The pilot did not detect water in the fuel when he did his fuel drain check of the aircraft tanks after the refuelling. The aircraft engine lost power when it ingested water contaminated fuel. After the engine failure, the pilot stalled the aircraft at a low height while manoeuvring to avoid a fence.