Asiana faults jet in SF crash

Asiana Airlines acknowledged in documents released Monday that its pilots failed to correct their fatally slow approach to a landing at San Francisco International Airport but also blamed the maker of the jet, saying it did not automatically maintain a safe speed.

U.S. accident investigators made public a filing in which the South Korea-based airline asserted that the Boeing 777 had major design flaws that led the pilots to believe it would keep flying at the proper speed and that failed to warn the cockpit crew in time when it did not.

Boeing Co. countered in its own filing with the National Transportation Safety Board (NTSB) that the airplane performed as expected, and the pilots were to blame for the July 6 crash because they stuck with a troubled landing.

The plane slammed into a seawall at the beginning of a runway during its final approach. The impact ripped off its back and scattered pieces of the jet as it spun and skidded to a stop.

In all, 304 of the 307 people aboard survived. A San Francisco-issued report contradicted a coroner's finding that a 16-year-old girl survived the crash and was killed by the vehicles. Instead, the city said Ye Meng Yuan died when she hit the ground after she was thrown from the back of the Asiana jet. 

Asiana acknowledged in its NTSB filing that the crew failed to monitor air speed in the moments before the crash and should have aborted the landing for another go around.

However, Asiana argued that the pilots and co-pilot reasonably believed the automatic throttle would keep the plane going fast enough to reach the runway — when in fact the auto throttle was effectively shut off after the pilot idled it to correct an unexplained climb earlier in the landing.

The airline said the plane should have been designed so the auto throttle would maintain the proper speed after the pilot put it in "hold mode."

Instead, the auto throttle did not indicate that the plane had stopped maintaining the set air speed, and an alert sounded too late for the pilots to avoid the crash, Asiana said. The airline added that U.S. and European aviation officials have warned Boeing about the issue, but it has not been changed.

In most other planes, idling the auto throttle would not disengage it for the rest of a flight, aviation safety consultant John Cox said.

Cox, president and CEO of Safety Operating Systems and a former airline pilot and accident investigator, likened it to the cruise control in a car. If a driver sets it for 55 mph and then accelerates to pass a car, the driver would expect the cruise control to re-engage when the speed slows to 55 mph again.

Asiana wrote that the pilot flying the plane, Lee Kang Kuk, had been trained to recognize the throttle issue with a 777. The most recent training was three months before the accident, and the instructor specifically used a landing at San Francisco airport as an example.

The NTSB previously said the pilots showed signs of confusion about the 777's elaborate computer systems. The agency has not determined an exact cause of the crash.

Boeing told the NTSB the airplane and all its systems were functioning as expected.

Al Jazeera and The Associated Press