In the wake of the Boeing 737 MAX accident, the world has focused again on the Lion Airlines accident five months ago: if there are similarities between the two aircraft crashes, it will further prove the Boeing plane has a fatal loophole.
Yesterday (March 20), Reuters learned that the recording of the black box of Indonesian Lion Airlines flight JT610, which crashed into the sea on October 29 last year, was made public for the first time: the crew was still searching the operating manual before the plane crashed. But in the end, no solution was found.
Observers noted that the accident's investigation team revealed on November 12 that Boeing's manual on the flight did not say anything about how to deal with such a situation.
As a result, the last 13 minutes of life on board the Lion seemed to rest on a 0% chance.
"time is up, the question is not finished."
Reuters did not get the audio recording, nor did it record the text. Instead, it restored the scene with information from three anonymous investigators. It was the first time what had happened in the cockpit 13 minutes before the Lion crash.
According to the Observer Network, combined with the initial report of the black box released by the Indonesian authorities in November last year, the incident was restored as follows:
On October 29, 2018, at 06:20 local time, Lion Airlines took off from Jakarta under the command of the Indian pilot, who was in charge of wireless communications.
2 minutes later, the co-pilot reported "operational problems" to the air traffic control department. According to a source quoted by Reuters, the co-pilot found an anomaly in the airspeed meter at the time. Another source said the exception only appeared on the co-pilot's dashboard, and there was no indication of the location on the plane. The captain then asked the co-pilot to check the operating manual, which contained instructions for handling unusual conditions during the course of the aircraft's voyage.
Next 9 minutes, Lions Airlines flight JT610 cockpit appeared "man-machine war." The electronic system on board warned the pilot that the plane was "stall" and the head of the plane began to fall. The captain tried to climb the plane, but the electronic system still showed "stall" and the nose continued to fall.
There was little talk in the cockpit. Eventually, the captain asked the co-pilot to fly the plane and began to look through the manual personally.
A minute before the crash, the captain asked air traffic control to clear routes below 3000 feet and request a 5000-foot flight altitude to be approved. This is also the captain's last words, the co-pilot prayed "Allah first".
The plane then crashed into the sea, killing all 189 people on board.
The site of the recording and restoration of the black box basically coincided with the details of the preliminary investigation report at the end of November last year. According to flight altitude records, the Lion Airlines crash plane quickly fell two minutes after takeoff, then pulled up to more than 3000 feet, rising and falling at an altitude of ups and downs, and finally plummeted.
A diagram of the altitude of the Lion Airlines crash plane after take-off
Reuters said the crew were "desperate" in the last few minutes. One of the sources commented, "it's like an exam, 100 questions, time is up, you only answer 75." So (they) panic, that's a time-bound situation. "
0% probability
The description of "scrambling through the manual" is also consistent with earlier investigation reports.
The accident's investigation team told Reuters on November 12 that, combined with the records of the black box, the team believed one of the causes of the crash was an anomaly in the plane's "angle of attack sensor" data. And a new "stall-proof" system installed on board has an automatic head-down (automated).
Nose-down system). According to Boeing, the system on the 737 MAX has the ability to bypass driver control, and automatically repeats the descent process after five seconds, even by manually pulling the head up.
The investigation team noted that neither the operating manual nor the training program provided by Boeing mentioned the newly installed system.
According to a November 10 memo from Southwest Airlines'(Southwest Airlines), the system was "designed only to take into account the rare circumstances of manual driving," so pilots "shouldn't have seen the system in real flight." As a result, Boeing chose not to include an introduction in the MAX operating manual.
In the wake of the Lion Air crash, both American pilots' unions said there was a potential risk for the Boeing 737 MAX's "mobility enhancement system," (MCAS), but was not fully explained in the pilot's operating manual or training. Union leaders said the risk and response were not addressed in any document on the MAX series.
If the above information is true, Lions Airlines flight crew is unable to find a solution in the manual.
There are "obvious similarities" between the two air crashes
In the light of the accident, Ethiopian authorities said on the 17th that after preliminary analysis of the black box, the air crash and Lion Airlines accident have "obvious similarities."
3月12日，埃航坠机现场发现波音操作手册中的一页
“数据已经恢复成功，美国团队和我们（埃塞俄比亚）的团队都验证了数据。我们感谢法国政府（黑匣子检测地），三四天后我们会公布更多消息。”埃塞俄比亚交通部一位发言人表示。
但在华盛顿，美国官员向路透社称，该国政府部门尚未验证数据。
当天，位于波音工厂所在地当地媒体、《西雅图时报》还扔出重磅曝料：波音737 MAX飞行操作系统的安全认证，是自己完成的。此外，为了吸引更多航空公司买家，波音甚至隐瞒了安装新型飞行系统一事，减少飞行员培训，以节省巨大成本作为卖点。
MCAS系统示意图
文章指出该机型电子系统的漏洞：为防止飞机空中失速，飞行控制系统可以转动飞机的平尾，让机头朝下。但客机服役后，该机型新功能MCAS转动速度要比初始安全评估标出的速度高出四倍多。
这就造成飞机在触发MCAS系统后，机头下坠幅度将出乎驾驶员意料，这一切似乎在狮航事故中得以体现。
波音和美国联邦航空管理局至今未对《西雅图时报》这篇文章作出回应。19日，波音CEO在坠机事故发生8日打破沉默，对空难罹难者家属表示慰问，并重申波音公司对安全的承诺。
昨日美股开盘，波音小幅高开，截至发稿涨0.38%，报374.86美元/股。