The crash of an Asiana Airlines jetliner at San Francisco International Airport appears to be "an unfortunate textbook example" of questionable cockpit decision-making during what pilots call "short final" approach, one expert said.
"Because of the high tempo of operations, there is no way you can recover," said Najmedin Meshkati, an engineering safety expert at USC. "That's why all your decisions have to be perfect. There is no time for discovery of your error or recovery from your error."
As Asiana Airlines Flight 214 approached the airport 400 feet above San Francisco Bay, it was flying too low and too slow, crash investigators have said. That should have been a warning to the pilot to abort the landing and make another attempt, aviation experts said.
The key part of the airport's automated landing system wasn't working, which forced the pilot to visually guide the massive jetliner onto the runway.
But pilot Lee Kang-kook didn't abort. What was even more baffling is that he and the more experienced co-pilot next to him didn't discuss their predicament. Cockpit voice recordings indicated that the two didn't communicate until less than two seconds before the plane struck a sea wall and then slammed into Runway 28L.
Lee was being supervised by the Capt. Lee Jung-min, though he too did not call for a go-around until 1.5 seconds before the crash -- far too late for the abort to occur. By then, the aircraft's systems were already warning that it was near stall, a condition in which it does not have enough lift to continue flying.
Only seconds earlier, Lee Jung-min had called for more engine power, but that also came too late.
Michael L. Barr, an aviation safety expert and former military pilot who teaches at USC, said the powerful engines on big jetliners can take up to 10 seconds to go from idle to full thrust.
"Ten seconds when you are low to the ground is like a lifetime," he said.
At three seconds before impact, investigators said, the jet's speed dropped to 103 knots and the engines were spooling up but still at only 50% of full power. The jet's aft fuselage clipped the sea wall and the plane slammed into the ground, killing two and injuring dozens more.
Investigators and aviation safety experts focused Monday on why the crew did not recognize the danger they faced and take action.
The lack of the automated systems should not have been a problem, said Jared Testa, chief flight instructor at Embry-Riddle Aeronautical University's Arizona campus.
"In the U.S., pilots are trained in stick and rudder skills and looking out the window of the airplane," he said. "A visual approach should not be unfamiliar to a pilot. They are taught that from the very beginning. We instill the idea of stable approaches from day one."
The National Transportation Safety Board is in the process of interviewing all four pilots aboard the aircraft, the two at the controls and two relief pilots for the long flight. Deborah Hersman, chairwoman of the NTSB, said Monday that investigators will closely examine the crew's coordination in the cockpit.
"We're looking at what they're doing and why they were doing it," Hersman said. "We want to know what they understood."
If communications in the cockpit broke down, investigators and researchers will be looking for company policies or even cultural issues that may have caused the problem. Aviation safety studies have documented that in certain cultures, junior pilots are reluctant to question authority, which violates the entire concept of cockpit management, Meshkati said.