Читать книгу Air Disasters: Dramatic black box flight recordings - Malcolm MacPherson, Malcolm MacPherson - Страница 34

USAir Flight 427, a Boeing 737-3B7, departed Chicago-O’Hare Airport for Pittsburgh at about 6.10 p.m. with two pilots, three flight attendants and 127 passengers. Flight 427 was approaching Pittsburgh for a landing on runway 28R when Pittsburgh air traffic control reported trafficin the area that Flight 427’s first officer confirmed by sight. The aircraft was levelling of at 6000 feet at a speed of 190 knots and rolling out of a 15 degree left turn with flaps at 1, with its gear still retracted and autopilot and auto throttle systems engaged, when the aircraft suddenly entered the wake vortex of a Delta Airlines Boeing 727 that preceded it by approximately 69 seconds and 4.2 miles. Over the next three seconds Flight 427 rolled left to an approximately 18 degree of bank. The autopilot initiated a roll back to the right as the aircraft went in and out of a wake vortex core, resulting in two loud ‘thumps’. But the first officer manually overrode the autopilot without disengaging it by making a large right-wheel turn. The aeroplane started rolling back to the right, but it never reached a wings-level attitude.