According to Aviation Week Intelligence Network's Fleet Database, the Asiana Airlines 777 involved in yesterday's accident was a 777-28EER, Serial No. 29171/Line No. 553, built in February 2006 and delivered to Asiana Airlines in March 2006. The aircraft was equipped with Pratt & Whitney PW4090 engines. As of April 2013, the airframe had accumulated 35,746 hr. and 5,185 cycles.
The aircraft was the seventh out of 12 777s that Asiana received between February 2001 and July 2012. Asiana has not disposed of any 777s it operated. The carrier has one 777-200ER on order.
While this is the third 777 lost in an accident or incident, four more 777s have been permanently withdrawn from service for parts, bringing the total number of 777s permanently out of service to seven. A total of 1,120 777s have been built so far.
Incidentally, the accident aircraft's tail number, HL7742, is oddly similar to HL7442, a Korean Air Lines 747-200B that crashed into the Okhotsk Sea in September 1983 after being shot down by a Soviet fighter.