The pilot decided to undertake a flight departing from Moutiers private aerodrome accompanied, for the first time, by a passenger. The take-off weight was close to the aeroplane’s maximum take-off weight. The pilot took off on downsloping runway 35 which had been mowed two days earlier. During the take-off run, the pilot realised that the take-off run distance had increased and that the aeroplane was sluggish. He thought that he would not be able to stop the aeroplane before the obstacles situated beyond the end of the runway and continued the take-off. After the main landing gear struck the top of the fence, the pilot landed in a field in line with the runway. The nose gear failed on running into a hole.