Air investigators 'set priorities to maximize safety improvements'

AIR safety investigators receive 8000 reports each year on accidents and incidents among aircraft flying in, to or from Australia.

But unlike the media, which often assumes every technical problem is a safety breach, Australian Transport Safety Bureau staff must sift through and decide which reports are worthy of investigations.

A quick look at the bureau's weekly summaries shows how daunting a task this can be.

The summary for the week ending August 1 is 15 pages long and includes everything from malfunctioning autopilots on jumbo jets, lightning strikes to 737s, to defective landing gear and bird strikes on small aircraft.

"Everything that gets reported to us is basically assessed against the Act and regulations in terms of whether it meets the definition of a transport safety matter," ATSB aviation safety investigation director Julian Walsh said this week.

"Everything is recorded in our database ... If it's in our weekly summary, it's something we've assessed as being an accident or incident. In rough terms last year, I think we had about 8000 of those."

Mr. Walsh said ATSB prioritized and made judgments about which investigations would be most valuable from a safety viewpoint.

He said the board narrowed down the number of investigations to about 80 each year.

Priorities included fare-paying passenger operations and fatal accidents.

"There's a hierarchy of what we investigate starting with high-capacity regular public transport to low-capacity RPT, charter, and it works down the list to No7 or eight, which is sport and high-risk recreation activity," he said.

"I don't say we never investigate (that category) but we're less likely to do those."

Not on the ATSB's agenda are minor technical failures, even in big aircraft.

This explains why some "safety" breaches reported by the media in the past two weeks are not under investigation.

"Those sorts of things are reported to the Civil Aviation Safety Authority," he said.

"If there's some sort of maintenance defect, or a component that's got some sort of failure, that all gets reported through their system."

A recent hydraulic failure on a Manila-bound Boeing 767 had come under this category.

The failure involved a cracked component that had been quickly replaced and the aircraft returned to service.

"When we're only resourced to do the 80 investigations, how much real safety value are we going to get out of doing an investigation of that nature?" he said.

"The reality is we're not going to enhance the system significantly by looking at those sorts of things. I wouldn't want to underplay any sort of occurrence, but these sorts of technical things do happen and you would expect these minor things to be happening, with the level of airline activity around the world."

http://www.theaustralian.news.com.au/story/0,25197,24181430-23349,00.html

Fonte: Flight Safety Information 19/08/2008.