Air crash investigators hit back

Gene Crafar (left), John Mennie and Simon Green, who were killed in the Taumarunui crash.

Transport accident investigators have rejected damning criticism from the aviation industry, saying a recent international audit gave them a "clean bill of health".

The Transport Accident Investigation Commission (TAIC) was criticised by the Aviation Industry Association after last week releasing a second report into a fatal helicopter crash at Taumarunui in 2001 which exonerated two engineers who had previously been found accountable.

The commission's first investigation found the accident that killed three men had been caused by defective maintenance work.

Its second investigation, started in 2003 after the initial investigation was found to be flawed, found the fault was a bend in part of the tail rotor assembly.

AIA chief executive officer Irene King said the industry had major concerns about the quality of TAIC's work.

"Too many investigations do not find the real cause," she said.

"Although TAIC investigators typically have distinguished aviation careers, the industry is not confident that they have all of the requisite skills and experience to test evidence, deal with conflicting information or fully understand some of the systemic issues that can be the hidden part of the iceberg of any accident.

"The unfortunate effect of defective investigations is that the real cause goes undetected and thus the main purpose of investigating accidents - which is to learn from them rather than blame anyone - goes unachieved."

The commission needed to carefully amend their legislation, overhaul their assurance programme and develop investigatory skills, Ms King said.

Commission chief executive officer Lois Hutchinson was surprised the AIA had major concerns and said she did not think the commission needed a major overhaul. The commission received "a clean bill of health" in an audit by the international civil aviation organisation in March.

Ms Hutchinson said she could not provide figures for how many investigations found an accident's probable cause, as opposed to a definitive cause, but the commission did say if it could not find a cause.

Sometimes a cause could not be found because not all parts of a wreckage could be recovered, she said.

"At times we can only speculate and we are very cautious - more so since the Taumarunui helicopter crash - about speculating."

"We are aware that the AIA would like us to hold public hearings," she said.

"We don't have the capability to hold public hearings in every case and we also have this issue of protected disclosure so it's very difficult for us to hold an open hearing and have people stand up and speak because they would be in breach of our legislation."

The commission did not have its own laboratories but called on scientific expertise through industrial research and contractors.

There were problems trying to recruit investigators, as there was a shortage, she said.

"Even if we were given more money we wouldn't necessarily be able to go out and spend it as such."

- NZPA