The aircraft was carrying out a night flight to a strip lit by portable fluorescent lights. These lights were spaced 190 metres apart along the length of the strip. During the approach the left main gear struck rising ground, which formed the end of the built-up strip surface, approximately 29 metres short of the threshold. The left main gear drag brace failed and the oleo leg was bent, however, the gear did not collapse and the landing was completed without further incident.
The investigation revealed that the strip had been lengthened but the operator had not been notified of the change. The available portable lights had been evenly spaced along the length of the strip. However, due to insufficient lights being available, the spacing between them exceeded double the prescribed spacing and the threshold was inadequately marked. The pilot was not aware of the length and spacing anomalies. Consequently, because of these anomalies, he was presented with a false perspective of the angle of approach and misjudged the approach.