Tuesday, May 12, 2009

Wheels-up C-17 crash caused by pilot error

Article in Airforce Times by Bruce Rolfsen 8 May 2009

A C-17 Globemaster military transport crash plane landed at Bagram Airfield in Afghanistan January 2009 because the crew failed to lower the landing gear. Whilst no one was hurt it took the efforts of the efforts of more than 200 people, a 120-ton crane and airbags to lift the plane high enough to lower the landing gear so that it could be moved. Even so the repair bill was $19 million and the airport was out of action for about 30 hours.

Accident investigation board president Col. Richard D. Anderson is quoted as saying "Had they lowered the gear, the mishap would not have occurred." The report says the aircrew failed to follow checklist procedures, which is a "basic Air Force rule." But it also says the crew were distracted and others, including air traffic control, made errors.

Events identified in the report include:

* The automated 'ground proximately warning system' that would have instructed the crew to lower the wheels was apparently accidentally turned off;
* The airfield’s approach radar was not working so the crew were using visual flight rule, requiring more focus on plane speed and altitude; and other aircraft.
* To help spot mountain ridges surrounding Bagram and other aircraft, the pilots put on night-vision goggles.
* When the plane was about three miles out the crew radioed their “short final” to prompt the control tower for clearance to land, but got no response.
* 28 seconds before landing they radioed the tower again “short final,” this time getting clearance to land.
* Controllers failed to make the required reminder call — “Check wheels down.”
* The plane was flying at 172 mph on approach, 42 mph faster than approach rules called for, which should have prompted an aborted landing.
* None of the three pilots realised that they had missed to go through the “before landing checklist.”
* With the landing gear still up, the plane’s ground warning system should have sounded out “too low gear.” However, it didn’t activate because the pilots had accidentally turned it off (according to investigators).

I will look out for more information on this accident. It maybe that the crew are being lined up as the main culprits, but clearly there were errors by others and technical failures. Also, there may be some systemic and/or cultural problems, as evidenced by the fact the crew were prepared to land when speed was too high, which is especially significant given that one of the crew was an instructor monitoring one of the others.

Also, it is noted that this is not the first time this type of accident has happened.

Andy Brazier

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