Early findings in the Asiana 777 crash investigation

6 July 2013; Asiana Airlines 777-200ER; HL7742; flight 214;San Francisco, CA: The aircraft was on a schedule international flight from Seoul, South Korea to San Francisco, and the rear of the aircraft struck a seawall just short of the runway while landing. The tail section broke apart, and both horizontal stabilizers and the vertical fin separated from the aircraft. Both engines and the main landing gear also separated from the aircraft.

In the photo on the right, the vertical fin and horizontal stabilizers (also called the tailplane) are very early in the debris trail, and in the overrun areas just before the runway threshold.
The aircraft caught fire after it came to rest, but not before all of the crew and most of the passengers were able to escape. All 16 crew members survived, but two of the 291 passengers were killed.
In the NTSB press conference on Sunday July 7th, the day after the accident, the NTSB revealed a variety of preliminary information about the sequence of events that led to the crash, including the following:

• Prior to the crash, the aircraft did not experience any significant problems with performance or with its systems,
• Both the cockpit voice recorder and the flight data recorder (the black boxes) were recovered and were being evaluated by the NTSB
• The pilots had stated that their intended landing speed was 137 knots, but at the time of the crash the aircraft was flying at a substantially slower speed,
• The data indicate that the throttles were at idle and the airspeed slowed below target approach speed during the approach,
• Sound of stick shaker (indicating an impending stall) began about four seconds prior to impact,
• The throttles were advanced a few seconds prior to impact and the engines appear to respond normally.
• The crew stated an intention to execute a go around about 1.5 seconds before impact, and
• The crew did not transmit any kind of distress or emergency call.

On Sunday, Asiana Airlines also revealed that the pilot responsible for performing the landing had landed other aircraft at San Francisco's airport, but the accident flight was the first time the the pilot had attempted to land a 777 at that airport.
Given the distribution of the wreckage in the debris trail, both horizontal stabilizers, the vertical fin, and at least two of the three landing gear separated very early in the crash sequence, making it very unlikely that the crew would have been able to keep the aircraft on the runway.
Crash video released
On Sunday, CNN released a video taken from near the airport that shows the entire crash sequence. The video shows that the aircraft rotated counter clockwise after the tail section separated, and the rear of the fuselage was lifted up at least 20 feet before it slammed down on the ground. It is possible that much of the serious structural damage seen at the rear of the fuselage, including a ruptured aft pressure bulkhead, occurred when this part of the plane slammed down toward the end of the crash sequence.
Status of landing aids
While one of the navigational aids on the landing runway (28L) that provides glide slope guidance was not operational, this should have been known to the crew because it was published as a notice to airmen (NOTAM), and there were several other options that the crew could have used for approach guidance. Since aircraft were landing under visual flight (VFR) rules at the time, there was no requirement to use these landing aids.

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NTSB photos

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Dr. Curtis and Capt. Tom Bunn discuss the crash
The day after the crash, Dr. Curtis of AirSafe.com and Capt. Tom Bunn of the SOAR fear of flying program, who both spent several hours on the day of the crash on cable news programs providing expert commentary, discussed the media's response to the accident and shared their thoughts on the early reports of the crash.

Additional information
AirSafeNews.com article 13 July 2013 article
AirSafeNews.com article 10 July 2013 article on the role of the autothrottle
Other Asiana plane crashes
Other 777 plane crashes
Accident details from Aviation Safety Network
Wikipedia page on this accident
Photos: BBC, Getty Images, NTSB