Sunday, August 31, 2008

Aircraft separation incident: Delta Boeing 737 and Transaero Boeing 747

Delta Air Lines B737 tailAn aircraft separation incident over the Atlantic Ocean involving two passenger aircraft is being investigated by the U.S. National Transportation Safety Board (NTSB). The two aircraft involved in the incident were a Boeing 737-800 operated by Delta Air Lines, and a Boeing 747-400 operated by Russian carrier Transaero. No one was injured.

According to information provided by the NTSB, on August 28, 2008, at approximately 18:37 Atlantic Standard Time, the two aircraft "came within zero feet vertical and 1 minute lateral separation at an altitude of 33,000 feet about 179 miles north of San Juan, Puerto Rico." The incident occurred over the Atlantic Ocean in a non-radar environment where 15 minutes of lateral separation is required.

The NTSB says that the Transaero 747 "descended 200-300 feet after receiving an alert from its Traffic Collision Avoidance System (TCAS)." The NTSB statement did not mention what action was taken by the Delta aircraft.

The Transaero Boeing 747-400, operating as Flight TSO 554, was en route from Moscow Domodedovo International Airport to Punta Cana International Airport in the Dominican Republic. The Delta Air Lines Boeing 737-800, operating as Flight DAL 485, was en route from John F. Kennedy International Airport in New york to Piarco International Airport in Trinidad.

UPDATE Feb. 23, 2009: The NTSB reports probable cause for this incident as follows: "The San Juan CERAP controllers failure to ensure the two aircraft were properly separated using non-radar separation standards."