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Jetliner crashes in Ethiopia, killing 157 from 35 countries |
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Ethiopia/
South East of Addis Ababa near Ejere
Town
On
March 10, 2019, at about 05:44 UTC,
Ethiopian Airlines flight ET-302,
a Boeing 737-MAX 8,
Ethiopian registration ET-AVJ,
crashed shortly after takeoff from
Addis Ababa Bole International Airport (HAAB), South East of Addis Ababa
near Ejere Town. The flight was a regular scheduled international
passenger flight from Addis Ababa to Jomo Kenyatta International Airport
(HKJK), Nairobi, Kenya. There were 157 passengers and crew on board. All
were fatally injured, and the aircraft was destroyed. Ethiopian air crash investigators are adding to the pressure on Boeing to prove that they have truly understood and fixed flaws in the flight control system of their new 737 MAX series of jets. And they don’t seem ready to accept that that will happen without renewed scrutiny of that system by international regulators. In a interim report on the crash of Ethiopian Airlines flight 302 on March 10 that killed 157 people the investigators said that the pilots had followed recommended emergency procedures, but their efforts were overpowered by Boeing’s rogue Maneuvering Characteristics Augmentation System that repeatedly forced down the airplane’s nose. The report leaves no doubt that the Ethiopian flight was doomed by the MCAS system in exactly the same way that Lion Air Flight 610 was brought down last October over Indonesia. The Lion Air pilots, like the Ethiopian pilots, desperately tried to regain manual control of the airplane during the early ascent but the MCAS system repeatedly countered their efforts. The two crashes have taken a total of 346 lives. There is no precedent in recent aviation history for a new model jet to have two catastrophic crashes within five months apparently caused by the same flaw. After Lion Air, Boeing presented the problem as one of training the pilots. If the pilots were trained to respond to a problem with the controls they could deal with it. Boeing did not concede that the primary problem was technical, a faulty sensor reacting with the MCAS, not human. If they had acknowledged that the problem lay with the airplane, not the pilots, the entire fleet would probably have been grounded, as it eventually was. Instead, Boeing implied – amazingly – that even with the problem left unfixed the airplane remained safe to fly. This complacency was shattered when the Ethiopian pilots followed Boeing’s procedure and still the airplane nosedived to oblivion. The comments from the Ethiopian authorities underline the failure of both Boeing and safety regulators to understand and respond to the seriousness of what the Lion Air crash had disclosed: That a faulty sensor feeding data to the MCAS system had switched control of the most powerful control surface on the airplane, the horizontal stabilizer, from the pilots to the computers. The timeline of how Boeing and Federal Aviation Administration safety inspectors responded to the Lion Air crash now looks increasingly damning. On February 7, some three months after the crash, Boeing presented a bunch of proposed changes to the MCAS system to the European Aviation Safety Agency. Under bilateral arrangements between the FAA and EASA all safety certification steps are normally taken together. And on March 7 – three days before the Ethiopian crash – Boeing took what they believed would be the final step, issuing for approval new pilot training procedures for the MAX-8 that would include an understanding of the MCAS system and corresponding details of that system were to be included in flight manuals. One of the most startling revelations that followed the Lion Air crash was that pilots had never been briefed on or trained for dealing with the MCAS system that was, essentially, contained in a few lines of new software. At that point neither Boeing nor any safety regular had entertained the idea that the world fleet of MAX-8s, approximately 370 airplanes, should be grounded. That all changed within two days of the Ethiopian crash. China, the largest operator of the MAX-8, unilaterally grounded its fleet. Soon after the rest of Asia, then Europe and Canada, followed. That was in stark contrast to the FAA’s first response on the day after the Ethiopian crash when they announced, “Our review shows no systemic performance issues and provides no basis to order the grounding of the aircraft.” Boeing echoed that statement. And that makes it even more remarkable that this week the FAA stated that the grounding would be unexpectedly prolonged because Boeing’s latest proposed fixes had not satisfied a panel of safety inspectors and needed “additional work.” In a separate statement Boeing said, “We are working to demonstrate that we have identified and appropriately addressed all certification requirements and will be submitting for FAA review once completed in the coming weeks.”
One feature of the proposed fixes that is already known focuses on the sensors that measure the airplane’s angle of attack – the angle at which the airplane pitches up or down from its level flightpath. These sensors are a comparatively simple instrument – they protrude like short tubes from the nose of the airplane. This position makes them vulnerable to both accidental impacts while lining up with an airport gate or from bird strikes. That is one reason why regular maintenance checks should be made of them. But Boeing’s fix for preventing a sensor from triggering the MCAS system via false data readings – in other words, indicating the approach of a dangerously high angle of attack and prompting it to correct it by pitching down the nose – is to equip every MAX-8 with a second sensor. If one sensor is flawed a “disagree” light in the cockpit would warn pilots of the problem. However Airbus equips its rival to the 737, the Airbus A320, with three sensors and even that did not prevent a fatal crash. In November 2008 a seven-man crew was flight testing an A320 owned by Air New Zealand over southwestern France. During a landing approach over water the Airbus went into a slow-speed aerodynamic stall. The nose pitched up by 57 degrees and it plunged into the Mediterranean, killing all on board. An investigation found that the sensors had been
damaged before the flight when the airplane was washed with powerful
water jets. One sensor had provided the pilots with correct data and the
other two were feeding false data. The flight control computers accepted
the majority false readings and rejected the correct one.
Interim
Investigation Report on Accident to the B737-8 (MAX) Registered ET-AVJ
operated by Ethiopian Airlines on 10 March 2019
На борту было
157 человек из 35 стран. В
том числе трое россиян-туристов. Все
погибли. Серия стала самой
продаваемой за всю историю Боинг - заказано и летает уже в сумме 1570
лайнеров.
10.03.2019/ 05:44 UTC За да се справят със ситуацията е необходимо да изключат самата система MCAS чрез двете ключета за нея като ги поставят в положение „cutoff”, но дори тогава, те ще трябва да разполагат поне с десетина секунди, докато компютрите отреагират на промяната. При недостиг на височина, с треперещ в ръце лост за управление и поредица от включващи се предупреждения, когато системата надделява над опитите на пилотите за ръчно управление на полета, те са в безизходица водеща до катастрофа. Разследването продължава. Катастрофата е втора по рода си с Боинг след тази на "Лайън Еър" в Индонезия на 29.10.2018, отнела живота на 189 души. След тази катастрофа постепенно моделът
Боинг-737 MAX-800 бе приземен в целия свят, а акциите
на фирмата Боинг рязко се снижиха.
Скандални разкрития в доклада за
производството на "Боинг 737 МАХ" |
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10.03.2019 - AircrashConsult |
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