After take off from Porgera the aircraft proceeded West towards a gap which required 9500 feet for passage. The pilot noticed that the aircraft was not able to outclimb the rising terrain. He turned left, however, for undetermined reasons the helicopter descended. A right pedal turn was made through 180 degrees and although then tracking down the mountainside, the pilot realised he would not clear the terrain ahead. He carried out a forced landing amongst trees in steep, rough terrain. The helicopter may not have had sufficient performance to complete the attempted operation. The ambient conditions, particularly temperature, could not be determined.
