Previously on this topic: “Is It Time to Worry About the Boeing 737 Max?”, “A Shorter Guide to the Ethiopian Tragedy and the 737 Max,” “What Was On the Record About Problems With the 737 Max,” “‘Don’t Ground the Planes, Ground the Pilots,’” and “The Implications of the 737 Max Crashes.”
As the investigation goes on, additions for today:
1) The Seattle Times. Over the decades The Seattle Times has been a leader in aerospace reporting, no doubt in part because of Boeing’s huge presence in the area. In the 1980s, our friend Peter Rinearson won a Pulitzer prize for his Times coverage of the Boeing 757. In recent years our friend Dominic Gates has broken a number of important aerospace stories for the Times.
His latest one, today, is about the 737 Max and is very much worth reading in detail. Here is its summary of Boeing’s internal assessment of MCAS—the automated pitch-control system that is known to have been involved in the Lion Air crash in Indonesia last fall, and may or may not have played a part in this month’s Ethiopian Airlines crash.
Gates writes of the Boeing internal analysis, which he has seen and discusses with industry experts:
The 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.
- 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.
- Assessed a failure of the system as one level below “catastrophic.” But even that “hazardous” danger level should have precluded activation of the system based on input from a single sensor—and yet that’s how it was designed.
The whole story is worth reading carefully, as is all of Gates’s coverage.
(By the way, looking for a reminder of why local- and regional-based news operations matter? Look again at The Seattle Times on this topic.)
2) Veteran pilots, on the fundamental training question. I continue to learn from, and be grateful for, a stream of messages from professionals within the aerospace community, about their views on the 737 Max tragedies.
The first note comes from a long-time pilot for a major U.S. airline who flies a different model Boeing plane. It responds to a previous dispatch, “Don’t Ground the Planes. Ground the Pilots.” In that post, another long-time pilot, Wally Magathan, said that one technical approach would be to require all 737 Max pilots to stop flying until they had undergone additional training.
This pilot writes:
By way of background, I’ve been flying at [a major U.S. airline] since 1985, and am currently a 777 Captain. I have never flown any model of 737.
Here are a couple of my own considerations about the 737 MAX grounding:
First, had the two recent tragedies occurred within a few months of the first MAX deliveries, there surely would have been no debate about the wisdom of stopping operations with that aircraft until causes and solutions were clear.
However, apparently there have been more than 350 MAX aircraft put into service in the last two years. I have read that worldwide the MAX has flown more than 70,000 flights. So while it’s now clear that some Boeing engineers and FAA certification people made egregious and unfortunate errors with the MCAS system precisely as Mr. Magathan indicated, it seems quite unlikely to me that MCAS was a singular causation either of the recent crashes. [JF note: Extra emphasis on the word “singular” in this sentence. Given the redundant safety systems of modern aircraft, when they crash, the reason usually turns out to be a complex “accident chain” of mistakes or failures. Usually it appears that the “chain” leading to a crash could have been interrupted at any point—and the plane would not have crashed—if a mechanical part or sensor hadn’t failed, or if some person involved with the flight had made a different choice. For instance, in the ASRS reports quoted earlier, U.S. airline pilots noticed a pitch anomaly with their 737 Max planes—and switched off the automated systems, “breaking the accident chain,” and flew on.]
In short, if the MCAS system was flawed to the point that the 737 MAX was inherently dangerous to fly, it seems to me that pilots, NASA, FAA, and the airlines would have been screaming at Boeing long before the Lion Air crash.
At the same time, great focus has been placed on the fact that both accidents involved this new version of the 737. But given the astronomical numbers of airline flights every single day and the small number of aircraft types that make up the vast majority of the worldwide airline fleet, is it really that improbable that two accidents involving similar flight profiles and the same aircraft type might occur? Might we have something on the order of two Black Swan events here?
Last, the hair on my neck has been standing up since I heard news of the Ethiopian First Officer’s lack of experience. [JF note: the Captain on the Ethiopian flight was highly experienced, but reportedly the First Officer, the pilot sitting in the right-hand seat, has only 200 hours total flying time, which is hardly any at all.] As you probably know, numerous countries, not least Germany and Mexico, have long employed “ground up” training systems for airline pilots. [JF: In these programs, new pilots start practically from the beginning flying alongside experienced pilots, in the airline fleet. This is in contrast to the U.S. approach of having prospective pilots “build time” elsewhere—in the military, as instructors, as charter pilots, etc—before switching to the airlines.]
The selection process of U.S. airlines has always seemed far superior to me, but of course for many reasons our nation has long had the luxury of a far greater pool of available experienced talent.
One more note: This comes from a very long-time military pilot and instructor. He stresses that, even as technology changes, fundamental questions about approaches to training remain:
I am a retired B-52 pilot/flight instructor, ATP [Air Transport Pilot certification], with extensive other experience in regional airlines and as a Flight Safety instructor in King Air.
In 1968 Boeing modified the flight control system (stability augmentation system, as I recall) for half the B-52 fleet, which took several months/years to accomplish. I was an Air Force copilot at the time, and for several months we regularly sent our planes to depot maintenance or Boeing factories to install the new system. They simultaneously sent out factory representatives to each base to accomplish classroom training in the new system …
Each crew was briefed and given classroom training, but despite the effort, it was still possible to be assigned later to fly an airplane without notice which had the new system installed, and some confusion to be experienced. One of the aircrew reports you quoted echoed, 50 years later, the same complaint.
The fault, in my opinion, lies with the airlines involved and their associated training. Flight positions are coveted, nobody in one wants to rock the boat and admit his inadequacy. A recipe for accidents. The manufacturer, airline, and pilots themselves all share some of the blame for putting up with less than adequate training.
The Max versions of the 737 could/should be considered a different type aircraft which would require the type rating for that specific model, not just the basic 737.
In the Vietnam war, in 1968 the Air Force started augmenting flight crews flying the b-52D models in theater with other flight crews who had been retrained at Castle AFB from newer models. Even then for the first two flights in the D models in theater, an experienced pilot and navigator instructor on that plane flew (over the shoulder) along to insure adequate training in that plane. Boeing could do the same here, send avionics representatives along with each crew on a training flight to insure adequate training.
Bonus: This Twitter thread, by Trevor Sumner, is worth reading and considering.