As the investigation continues into the crash of Asiana Airlines Flight 214, the National Transportation Safety Board has given another update about what it found so far from the cockpit and flight data recorders. While the plane should have been approaching the runway at SFO at 137 knots per hours (157 mph), NTSB head Deborah Hersman said Flight 214 was "significantly below" that, "We're not talking about a few knots."

Flight 214 hit the seawall at SFO just before noon on Saturday, causing the plane to make impact with the ground then bounce and crash. Two passengers, a pair of 16-year-old students from China, were killed. Hersman also recounted the last seconds. From the AP:

Seven seconds before the crash, pilots recognized the need to increase speed, she said, basing her comments on an evaluation of the cockpit voice and flight data recorders that contain hundreds of different types of information on what happened to the plane. Three seconds later, the aircraft's stick shaker -- a piece of safety equipment that warns pilots of an impending stall -- went off. The normal response to a stall warning is to boost speed and Hersman said the throttles were fired and the engines appeared to respond normally.

At 1.5 seconds before impact, there was a call from the crew to abort the landing.
The details confirmed what survivors and other witnesses said they saw: an aircraft that seemed to be flying too slowly just before its tail apparently clipped a seawall at the end of the runway and the nose slammed down.

An American Airlines pilot with experience flying 777s told the AP that pilots "normally try to land at the target speed, in this case 137 knots, plus an additional five more knots."

The NTSB also released photos from the crashed plane itself as well as footage of it.

All previous Asiana Airlines crash coverage on SFist.