TAIC fail again to identify accident cause
The Chief Executive of Air Fiordland Mr Russell Baker said that the report issued today by the NZ Transport Accident
Investigation Commission regarding a non-fatal accident involving one of his aircraft ZK WWH in August 2005, was not
correct in its finding that frost on the wing was the cause.
“All the information available shows the aircraft took off with a clean wing and that the accident arose as a
consequence of the pilot experiencing unanticipated severe wake turbulence from the preceding aircraft” said Mr Baker.
Mr Baker said that as recently as yesterday, in a letter to the Chief Executive, he had urged TAIC not to conclude its
investigation and to make further enquiries.
The accident occurred when two Cessna 206 aircraft, both owned by Air Fiordland and carrying the same load, made an
early morning take off from Queenstown airport last winter. In accordance with normal practice and the air traffic
control clearance, the 2nd aircraft was about 600m behind the first aircraft when it began its takeoff roll. Immediately
the 2nd aircraft was airborne, the pilot suffered severe control problems and attempted to land immediately, damaging
the wing and the nose. There were no injuries.
“There is a very important safety lesson to be learned from this accident which relates to the separation distance
needed behind this particular type of aircraft. In certain conditions, such as the cold light winds that existed on the
day, 600m is just not enough,” said Mr Baker.
“Since the accident, other pilots had written to him and told him of their own experiences with the wake turbulence
caused by this type of aircraft. All said it was much more severe than they had expected.”
Mr Baker said that from the outset, TAIC investigators appeared to have formed a mindset that the cause was the failure
to clear overnight frost from the wing before taking off. However the wings of both aircraft, which were parked in the
same location overnight, were both cleaned twice.
“Some months ago, when I was sent the draft report, I urged the TAIC Chief Executive to appoint an independent reviewer
but to no avail. TAIC should have also seconded someone to their investigation team with experience in light aircraft
winter flying and should have conducted experiments. Had they asked for my help to undertake tests, I would have gladly
given it but they didn’t.”
Mr Baker who has over 9000 hours experience flying light aircraft most of it in this region expressed his concern
regarding TAIC’s poor track record of investigations.
“Unfortunately, although their obligations to maintain confidentiality of information can help some witnesses to speak
frankly, it means that their work is not open to proper scrutiny and challenge.
“Making wrong findings is not only unfair to those involved but more importantly, the actual lessons go unlearned.
“TAIC are too inclined to disregard the evidence of those involved in accidents as was illustrated by their recently
revealed dismal failing in blaming two aircraft maintenance engineers for a Tauramanui helicopter crash. In that case,
the engineers said from the outset that they had followed correct procedures.
“In this case, while my pilot acknowledges that despite his very considerable experience he was taken by surprise by the
wake turbulence from the preceding aircraft, I have no doubt at all that he properly cleaned the wing before leaving –
using the same procedures and same cleaning broom as the pilot of the first aircraft which did not experience any
problems.”
Mr Baker said there was an obvious explanation for the ice nodules photographed on the wing of the damaged aircraft
sometime after the accident. The airport rescue fire team had immediately sprayed the still sub-zero wing with water as
a precaution and the air temperature was still below freezing.
“No one should regard this report as explaining what happened to my aircraft or what could happen to theirs in similar
circumstances. TAIC need to make changes to their processes, soon.”
Ends