On 18 October 1966 during Operation Queanbeyan in Phuoc Tuy Province South Vietnam, an Iroquois helicopter of 9 Squadron RAAF crashed in hilly and difficult terrain. Initial rescue of some occupants of the aircraft was performed by a crewman. However, the rescue of the seriously injured second pilot was a more complex task. Private Cavanagh and Private Shore of C Company 5th Battalion, Royal Australian Regiment who were in the vicinity of the crash arrived in time to assist in the hazardous task of rescuing the trapped second pilot. Seconds after the aircraft crashed, fire broke out in the general area of the aircraft fuel cell and engine. By nature of the site. this fire started to move slowly forward through the passenger and crew compartments of the helicopter. The presence of crew weapons, aircraft armament and associated ammunition, together with a quantity of TNT explosive constituting part of the aircraft load, posed a significant threat to those performing rescue operations.
Conventional removal of the second pilot from the wreckage was quite impossible due to torsional misplacement of various aircraft components. The fact that a small tree trunk pinned the second pilot's right leg to some parts of the aircraft was a further complicating factor. Under guidance from the crewman, Private Cavanagh then assisted with bare handed clearing of portions of the nose of the aircraft to eventually free the second pilot from his precarious position. Moments later, fire engulfed the remaining portions of the nose section of the wreckage.
By his complete disregard for personal safety, Private Cavanagh, working in unfamiliar circumstance, materially assisted in a desperate situation, which, if allowed to develop would most certainly have resulted in the incineration of the helpless second pilot in the ensuing fire in the nose section of the aircraft.