 It was reported that many Libyan People's Air Force bombing raids were carried out at excessively high altitudes when met with anti-aircraft fire, so the attacks were not very effective.On 17 February 1986, in retaliation for the Ouadi Doum air raid by the French air force, a single LPAF Tu-22B attacked the airport at N'Djamena.That aircraft ran into technical problems on its return journey – American early warning reconnaissance planes based in Sudan monitored distress calls sent by the pilot of the Tu-22 which probably crashed before reaching its base at Aouzou (maybe hit by twin-tubes that fired at it from N'Djamena airport).