The safety culture that has built up in the commercial airliner industry means we learn from any accident, any incident. Also, if anything is in doubt, the industry errs on the side of caution: we know what happened with the Comet I. One unexplained fatal accident should mean action is taken - like grounding some or all of that aircraft type. And then came the recent crashes involving Boeing’s new 737 Max.
Indonesian Lion Air Flight 610 crashed into the sea minutes after taking off from Jakarta Airport last October; all 189 on board died. We were told that the airline should not have used the aircraft involved as it was not airworthy. Therefore it was some kind of operator error. But when Ethiopian Airlines Flight 302 fell out of the sky minutes after departure from Addis Ababa Airport eight days ago, doubts began to grow.
One by one, countries banned the 737 Max from their airspace. Ultimately, every one of the aircraft type was grounded. Suspicion fell on the aircraft’s MCAS, or Maneuvering Characteristics Augmentation System, which is new with the 737 Max. The new aircraft has a tendency to pitch nose up when climbing - which could lead to a stall. MCAS is meant to ensure that any such tendency is corrected, by pitching the nose down.
But what happens if the information fed to MCAS is misleading? It can be activated by a single sensor. You read that right. Faulty sensor feeds wrong information to the autopilot, that pushes the nose down, pilot disengages autopilot, MCAS engages, uses the same wrong information, pushes the nose down. Screwed either way. It’s potentially deadly.
Now consider this from the Seattle Times: “As Boeing hustled in 2015 to catch up to Airbus and certify its new 737 MAX, Federal Aviation Administration managers pushed the agency’s safety engineers to delegate safety assessments to Boeing itself … But the original safety analysis that Boeing delivered to the FAA for a new flight control system on the MAX - a report used to certify the plane as safe to fly - had several crucial flaws”.
Boeing did their own safety assessment on the 737 Max. Then they delivered their findings to the FAA, who signed them off. The FAA is, to aviation authorities around the world, the gold standard. If the FAA says it’s good to fly, it’s good to fly. Period.
But that Seattle Times report also makes claims which, if true, mean both Boeing and the FAA have serious questions to answer. Consider this: “[the original safety analysis] Understated the power of the new flight control system, which was designed to swivel the horizontal tail to push the nose of the plane down to avert a stall. When the planes later entered service, MCAS was capable of moving the tail more than four times farther than was stated in the initial safety analysis document”. Got that? There’s more.
“[the analysis] Failed to account for how the system could reset itself each time a pilot responded, thereby missing the potential impact of the system repeatedly pushing the airplane’s nose downward”. Put those two flaws together. That is very, very bad. Unsurprisingly, “The people who spoke to The Seattle Times and shared details of the safety analysis all spoke on condition of anonymity to protect their jobs at the FAA and other aviation organizations”. But the real sting in the tail was yet to come.
Take a deep breath. “Both Boeing and the FAA were informed of the specifics of this story and were asked for responses 11 days ago, before the second crash of a 737 MAX last Sunday”. The crash of Ethiopian Airlines Flight 302 could have been prevented. Boeing and the FAA were informed on the 6th. The Ethiopian Airlines crash came four days later.
With some understatement, the Seattle Times observes “Several technical experts inside the FAA said October’s Lion Air crash, where the MCAS has been clearly implicated by investigators in Indonesia, is only the latest indicator that the agency’s delegation of airplane certification has gone too far, and that it’s inappropriate for Boeing employees to have so much authority over safety analyses of Boeing jets”.
For the commercial aviation industry, marking your own homework ought to be out of the question. The consequences of doing so are now all too plain: 346 deaths, and serious questions for both Boeing and the FAA to answer. It appears that, in the rush to keep up with Airbus, a rogue aircraft has been let loose. That isn’t good enough.
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