On the night of 1 July 2002, BAL Bashkirian Airlines Flight 2937, a Tupolev Tu-154 passenger jet, and DHL International Aviation ME Flight 611, a Boeing 757 cargo jet, collided in midair over berlingen, a southern German town on Lake Constance, near the Swiss border. All of the passengers and crew aboard both planes were killed, resulting in a total death toll of 71.The official investigation by the German Federal Bureau of Aircraft Accident Investigation (German: Bundesstelle fr Flugunfalluntersuchung) (BFU) identified as the main cause of the collision a number of shortcomings on the part of the Swiss air traffic controller (ATC) service in charge of the sector involved, as well as ambiguities in the procedures regarding the use of the traffic collision avoidance system (TCAS) on board.:110A year and a half after the crash, on 24 February 2004, Peter Nielsen, the air traffic controller on duty at the time of the collision, was murdered in an apparent act of revenge by Vitaly Kaloyev, a Russian citizen whose wife and two children had been killed in the accident.



The Tupolev Tu-154 (Russian: Tyполев Ту-154; NATO reporting name: "Careless") is a three-engined, medium-range, narrow-body airliner designed in the mid-1960s and manufactured by Tupolev. A workhorse of Soviet and (subsequently) Russian airlines for several decades, it carried half of all passengers flown by Aeroflot and its subsidiaries (137.5 million/year or 243.8 billion passenger-km in 1990), remaining the standard domestic-route airliner of Russia and former Soviet states until the mid-2000s. It was exported to 17 non-Russian airlines and used as a head-of-state transport by the air forces of several countries.

The aircraft has a cruising speed of 850 kilometres per hour (530 mph) and a range of 5,280 kilometres (3,280 mi). Capable of operating from unpaved and gravel airfields with only basic facilities, it was widely used in the extreme Arctic conditions of Russia's northern/eastern regions, where other airliners were unable to operate. Originally designed for a 45,000-hour service life (18,000 cycles), but capable of 80,000 hours with upgrades, it was expected to continue in service until 2016, although noise regulations have restricted flights to Western Europe and other regions.