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Aim of inquiry is to learn lessons, not lay blame

AN air accident investigation, by international agreement, is carried out not to find out who is to blame. Its purpose is to find out what went wrong so the aviation world can apply, as quickly as possible, any lessons available from it to prevent a similar event from occurring again.

The inquiry into the Manx2 accident at Cork Airport will be no different.

After the inquiry has reported, if it looks as if criminality -- in the form of negligence or recklessness by individuals or companies -- might have been involved, it is up to the judicial prosecution service, or the civil aviation authority, to act through the criminal court.

Neither criminality nor compensation is the direct concern of the accident investigators.

There is a good reason why organisations like Ireland's Air Accident Investigation Unit (AAIU) avoid acting like a court: if they were to act like a criminal court, all those interviewed in connection with the accident could claim their right to silence, so the investigation would be impeded. But if, on the other hand, the accident happened because people made mistakes, this will become clear during the investigation.

Afterwards, it would be the job of the judiciary or the Irish Aviation Authority (IAA) to decide whether those mistakes were unintentional human errors, or the result of recklessness or negligence. The investigation process begins as soon as the IAA learns of the accident.

The AAIU sends experts to the scene of the accident, which will already have been cordoned off by gardai.

They find and remove the two "black boxes", actually orange in colour. One is the cockpit voice recorder, which records everything the pilots say to each other via their headsets, but also communications on the radio with air traffic control, and all the ambient sounds in the flight deck, like engine noise, or even emergency system audible alerts.

Then there is the flight data recorder, which tells the investigators what the engines were doing, what the aircraft controls were doing, and the flight profile, which is recorded through inputs from instruments like the altimeter, airspeed indicator and compass.

Recordings of air traffic control activity will be frozen and kept as evidence. These contain radar traces that reveal the aircraft's horizontal flight path and its vertical profile as well.

Tapes of all communications within the air traffic control tower at Cork, and in the area control centre, as well as their exchanges with the Manx2 pilots, will be available to the investigators. The investigators also look closely at physical evidence, including everything from the nature of the crew and passengers' injuries to the type of damage the aircraft itself suffered.

The AAIU will also check the professional details of all the airline people involved in administering, enabling or carrying out the flight. Were the pilot's licences legal and up to date, showing the training they should have had recently? Was the aircraft's certificate of airworthiness valid, and are the records of its statutory maintenance requirements fully documented? Is the airline's operator's certificate up to date?

After about a month, the investigators usually issue an interim factual report.

THIS does not attempt to explain the reasons for the accident, but it does reveal the technical facts that have been established at that stage. There may already be a lot of technical information to make much clearer precisely what happened, but why it happened may not yet have become clear.

When the final accident report is published, usually between a year and two years after the crash, it presents a probable cause or causes, contributory factors, and it may contain recommendations from the investigators to the aviation authority for actions it could take to prevent such an accident happening again.

David Learmount is the operations and safety editor at Flightglobal (see www.flightglobal.com), and a former RAF flying instructor who flew Lockheed Hercules transport aircraft

Irish Independent