An Australian Transport Safety Bureau (ATSB) inquiry into the crash of a sight-seeing helicopter in Purnululu National Park on a flight to the Bungle Bungles on September 14, 2008 killing three young women has found that the pilot, who also died, may have been insufficiently skilled to hover close to a rock formation shown in the last image on the camera of one of the victims.
Her images also show that the scenic flight departed from the normal route and height and speed parameters set down by Slingair Heliwork (owned by former iron man Grant Kenny) for an aerial tour of one of WA’s most famous landmarks.
For reasons unknown the pilot, Christian Ion Catargiu, 40, took 19-year-old Jessica May Cousins, 20-year-old Sarah Louise Thomas and 20-year-old Whitney Pinney, all from Kununurra, to a hover point beside an alcove containing indigenous rock paintings and another object that cannot be identified from the photo.
The ATSB found that the helicopter was being flown out of ground effect, that is, with no benefit from rotor wash, but much too close to the ground to allow any guarantee that it could recover from any loss of engine power or other upset.
It crashed and burned 33 metres below the alcove.
The ATSB report discusses a range of scenarios for the loss of control, and mentions that willie willies (resembling miniature tornadoes) had been seen near the crash site in following days and could, according to the Bureau of Meteorology, have also formed on the day of the accident.
The helicopter and its rotor blades and engine were too badly damaged by fire and impact to support any unequivocal finding as to the cause, but the investigation found that by being flown so close to the ground yet beyond assistance from ground effect, and with little or no forward velocity, the type of small helicopter in use, a Robinson R44 Raven, may have had insufficient power for the manoeuvre being attempted by the pilot.
It also refers to the possibility that the pilot was flying outside his individual level of competence, leaving open the inference of that this crash was the result of a helicopter being flown outside its intended operational envelope by a pilot who didn’t fully understand what he was doing.
In what it describes as a “minor safety issue”, the ATSB draws attention to a lack of an Australian requirement for endorsement and recurrent training on Robinson helicopters to “specifically address the preconditions for, recognition of, or recovery from the loss of main rotor power”.
These would not be minor issues for the relatives of those killed.