Boeing blamed for Turkish Air crash

The crash of a Turkish Airlines plane near Amsterdam last year was caused by a known fault with the model's altitude-measuring system and could have been prevented by the pilots, Dutch investigators said.

"The problem with the radio altimeter in Boeing 737-800 airplanes was an issue for several years at multiple airlines, including Turkish Airlines, and was known to Boeing Co. and authorities," Dutch Safety Board Chairman Pieter van Vollenhoven said at a news conference in The Hague today.

A misreading by the altimeter caused the plane's automatic pilot to idle its engines, he said. The airliner, with 134 people on board, lost altitude and crashed short of Schiphol airport on Feb. 25, 2009, breaking into three sections. Five Turkish citizens and four Americans were killed, including the pilots and three Boeing Co. employees who were on a business trip.

"If the pilots had reacted adequately to the warnings then nothing would have happened," Van Vollenhoven said. He recommended Boeing increase the reliability of the radio altimeter system.

The crew acted promptly to the threat of a crash, Turkish Airlines said today in an e-mailed statement, adding the 737-800 has an "error-prone design." It was impossible to prevent a crash once the plane stalled at an altitude of 460 feet (140 meters), the company said.

Radio AltimetersBoeing has taken steps to make errors by radio altimeters less likely and to help flight crews identify problems, the Chicago-based company said today in an e-mailed statement. "These changes will make what is a safe design even safer," it said. Radio altimeters determine height above terrain, as opposed to height above sea level.Boeing has fixed the problem in some airplanes, Van Vollenhoven said. Boeing is working on the issue for other airplanes, he added.One of the components of the radio altimeter system is made by Thales SA, Markus Leutert, spokesman for Thales, based near Paris, said by telephone. Tests performed afterwards showed the component worked flawlessly following the accident, he said.The radio altimeter's antenna was manufactured by Sensor Systems Inc., according to the report. A telephone call before business hours to Dave Brooks, media contact at the Chatsworth, California-based company, wasn't immediately answered.None of the parts of the radio altimeter system was made by Rockwell Collins Inc., spokeswoman Pam Tvrdy said by telephone.