According to the opposition sources, rebel MiG-21 and MiG-23 fighter jets, Mi-24 combat attack helicopters, 14 rebel fighter pilots, 50 technicians and hundreds of ground personnel, all stationed at the Benina air force base, were crucial in their defence of Benghazi from pro-Gadaffi offensive, launching multiple airstrikes during the first half of March on advancing Gadaffi forces in eastern Libya, with the hardest day of combat for the Free Libya air force being 19 March, when pro-Gadaffi forces tried to capture Benghazi. But rebel air force suffered heavy losses in process—according to opposition sources, between 1 March and 19 March, rebel air force launched a total of 38 combat sorties (nine of which were conducted by Mi-24 combat attack helicopters) against advancing pro-Gadaffi forces in eastern Libya, but lost in the process two fighter jets and one helicopter, suffering eight pilots and gunmen killed.