Air NZ finds landing glitch linked to 40 accidents

linked to 40 acidents… Boeing better make a move quick.
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Air NZ finds landing glitch linked to 40 accidents :
Experts who investigated an Air New Zealand flight that nearly crashed in Samoa believe they have found a landing equipment fault linked to 40 accidents worldwide.

It is believed to have caused a major air disaster five years ago.

The Air NZ Boeing 767 with 176 passengers on board was 10 seconds from hitting the sea off Samoa in July 2000 after its instruments told it to land 8.8km from Faleolo Airport.

The pilot pulled up 400 feet from the ocean after noticing lights from a neighbouring island.

Now the crew’s account has helped aviation authorities to discover a glitch that can be linked to up to 40 other accidents.

Air NZ flight operations vice-president Bryan Wyness said the findings would save lives.

The investigation revealed that a warning system that should alert pilots when the instrument landing system, ILS, is not working can be easily shut down with the flick of a single bypass switch on the ground.

On the Air NZ jet it had been switched off for maintenance but no one was aware the switch would shut down the warning system.

The International Civil Aviation Organisation responded to the finding immediately, issuing warnings and new rules to airports, airlines and air traffic controllers worldwide.

Air NZ and the Civil Aviation Authority have suggested that the US National Transportation Safety Board should reinvestigate a Korean Air Boeing 747-300 accident that killed 228 passengers and crew in 1997 when the jet crashed into hills near Guam.

The US report concluded that the probable cause was the pilot’s failure to brief his crew that the ILS system was out of order, after receiving a pre-flight notice.

Mr Wyness, who has been a pilot for nearly 35 years, said pilots were taught that if there was no warning, then the system was working.

The Korean Air cockpit voice recorder clearly shows that the pilots were confused about the state of the ILS moments before the crash.

The Air NZ emergency followed a similar pattern.

The plane went on to automatic pilot and followed the landing signal, a beam through which the plane flies. But the signal had been adjusted for maintenance and showed a deceptively wide beam in which the plane could fly with the pilots believing they were on course.

When the automatic pilot was engaged at 3000 feet, the plane began slowly to descend five miles too soon.

The airliner was at 400 feet when it should have been at 2000 feet before the three pilots saw the lights of the nearby island. Within seconds, they pulled up and landed the aircraft manually.
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link: http://www.nzherald.co.nz/storydisplay.cfm?storyID=2997762&thesection=n…