Вероятная причина: Увлекшись обходом грозы, отвлекаемые болтанкой, пилоты могли забыть включить ПОС. Самолет в грозе обледенел, для поддержания высоты полета требовался все больший тангаж, к выходу из грозы самолет потерял скорость и свалился.
А автоматическое включение ПОС или "орущая" сигнализация об облединении на А не предусмотрена?Вероятная причина: Увлекшись обходом грозы, отвлекаемые болтанкой, пилоты могли забыть включить ПОС. Самолет в грозе обледенел, для поддержания высоты полета требовался все больший тангаж, к выходу из грозы самолет потерял скорость и свалился.
За полтора витка? ~ 6000м за виток. Как такой "пирует" будет называться? Ни крутой и не плоский, скорее не управляемое пикирование. Уж больно круто получается. С лайнером не знаком, возможно ошибаюсь.Донецк-2 ?
За полтора витка? ~ 6000м за виток. Как такой "пирует" будет называться? Ни крутой и не плоский, скорее не управляемое пикирование. Уж больно круто получается. С лайнером не знаком, возможно ошибаюсь.
Спираль есть фигура управляемая, за исключением "затягивания" в крутое пикирование (спираль) из-за превышения скоростных ограничений. По этому типу не скажу, техника и аэродинамика ушли далеко, но к примеру на Л-29 такой эффект присутствовал. Моему инструктору как то пришлось с этим бороться. Хорошо, что в задней кабине сидел КЗ с хорошей физической подготовкой. Вытянули.в их случае штопор стал спиралью.
ANAC reported the flight had been planned to proceed via waypoint ROFER and then airway UM608. During departure the autothrottle was engaged, at 10,500 feet the autopilot was engaged too. About 4 minutes later the crew indicated they were turning left onto a heading of 356 degrees to avoid (weather).
23 minutes after takeoff the aircraft levelled off at FL310 at 0.74 mach and was turning right to return onto the original track. The aircraft accelerated with engine EPR at 1.92, the aircraft reached 0.775 mach, then the airspeed began to decrease with the autothrottle still in Mach mode. About one minute later, at mach 0.752, the autothrottle changed to MACH ATL mode, pitch and EPR increased, altitude was stable, engine N1 remained stable, but speed continued to decrease.
The crew attempted to reach Niamey Control Center to radio they were deviating around weather, a Royal Air Maroc Flight offered to relay the message, Niamey received the message, issued a squawk and requested estimates for waypoint MOKAT, however, no reply was received from the aircraft anymore.
The flight data recorder revealed that EPR and N1 fluctuations occurred on both engines for about 45 seconds, then over the next 25 seconds the EPR increased from 1.6 to 2.5 and decreased again twice, N1 varied between 70 and 91 percent, roll oscillations 4 degrees to the left and right occurred, autothrottle disengaged between the EPR oscillations 1.6 and 2.5.
About 65 seconds after the EPR/N1 oscillations began the airspeed had decayed to 203 KIAS/0.561 mach and the aircraft began to descend, 29 seconds later the autopilot disengaged, at that time the aircraft had lost 1150 feet of altitude, airspeed was 162 KIAS, 0.439 mach and both engines were nearly at idle.
Subsequently pitch and bank angles were subject to large changed, the aircraft's nose pitched progressively down to 80 degrees nose down, the aircraft rolled to 140 degrees left bank. About 20 seconds prior to impact both engines accelerated and reached near maximum thrust. The last flight data recorder data indicated the aircraft at 1601 feet (QNH1013), 384 KIAS, 58 degrees nose down, 10 degrees left bank.
The captain (47, ATPL, 14,268 hours total, 10,013 hours on type) was assisted by a first officer (42, ATPL, 6,900 hours total, 6,064 hours on type) and had flown several times into Africa including Ouagadougou. The captain had flown as captain of a MD-80 on behalf of United Nations in Africa for 456 flgiht hours.
The ANAC reported the MACH ATL autothrust mode indicates that the autothrust system attempts to achieve the target but needs a higher than EPR than permitted by active EPR Limit value.
The flight data indicate that the outside air temperature changed from -16 to -32 degrees C during the climb, there was no significant turbulence.
The ANAC reported: "Outside air temperatures below -20°C are often considered not to be conducive to airframe icing, in particular for stratiform clouds. Icing conditions, however, have been observed at lower temperatures in dynamic convective clouds. This type of zone can be particularly active and highly dynamic, creating risks of severe icing and/or severe turbulence."
The ANAC reported that the cockpit voice recorder tapes were broken into 4 major pieces, repairs were undertaken and the data were read out, however, are barely intelligible or completely unintelligible "at this stage of the investigation".
Спасибо. Попробую перевести - если что, то есть кому поправить.Промежуточный отчет. Не перевожу, чтобы не потерять детали: