It was using Clinton-era flight computers. This is a common problem in aerospace. New avionics can’t necessarily be trusted for mission-critical tasks. The Shuttle computers were basically IBM-360s, all the way into the 90s.
5 thoughts on “The 737 MAX”
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The problem with the 737 MAX is even apart form the virus outbreak, most of us dread taking an airline flight.
Also, it used to be that a ride on a regional jet was like the seat over the wheel hump of a school bus, but my last ride on one of the larger, 4-across 2-engines-under the wings Embraer was surprisingly pleasant.
What is real torture nowadays is a 737-8/NexGen/whatever-you-call it and its competition, the A321-SR. I guess I don’t fly very often, and it was a shock to be seated with the seatback of the seat in front in my face. Oh, every seatback has an entertainment screen where you can be occupied with the altitude readout, a dumb movie, even dumber reading content or a video game.
This is The Matrix come to life. You are at the same time immobilized yet distracted from your discomfort. Oh, and these jets with the screens have something the Embraer lacks — these stupid metal humps housing the nodes powering those screens that you cannot get a bag to fit under the seat that had just fit on a regional jet.
Yeah, yeah, cheap flights — if you book 6 months in advance. Boeing and Airbus and their airline customers — using your service is under circumstances a necessity, but not us are saying ooo, a 737 MAX with the fuel efficient LEAP engine, ooo, an A321 neo SR with the Pure Power geared turbofan. There is as much enthusiasm for your conveyances as there is for the Blue Bird school bus with the direct-injection diesel engine.
These idiots have forgotten that, in both 737 max crashes, the crew left the power levers(throttles) at max power all the way to the ground. In any powered vehicle, when you are going too fast, the first step is ‘reduce the power’. They both hit the ground at full throttle. Both crews forgot, or did not know, the first step. Too fast-apply less power. The computers worked exactly as they were designed. The crews failed. But you can’t collect money from their families. Boeing, on the other hand, has their hand in the US taxpayers pocket.
Yes and no. Yes the crew in both crashes performed abysmally. No because Boeing put them in a box beyond their abilities. What Boeing did with the 737 Max was create an airplane containing flight-critical failure modes that required an average to above-average pilot to properly diagnose and act on. In the US, this isn’t a problem, but in the Third World, it is. And since Boeing sells to the Third World, it has a responsibility to make sure its customers are adequately informed about the aircraft, and they fell down on that job (partially abetted by the FAA).
Did you read the part about the throttles? A go-cart would have been beyond their capabilities.
So what? They met all the legal requirements to be where they were. If they weren’t qualified to fly the 737 Max as-is, due to Boeing’s design failures that put mediocre pilots in over their heads in the face of an MCAS malfunction, then Boeing shouldn’t have been selling that airplane to those airlines.
I’ve heard variations on your argument for months – the crew of these two airplanes should never have been allowed to fly because they were so bad; nothing really wrong with the Max except lousy pilots who can’t recognize a simple runaway stab, etc. All of these arguments have been coming from pilots, not engineers. I’m a highly experienced engineer, specializing in the design of fly-by-wire flight control systems, including everything from handling qualities to airworthiness qualification to analysis of mechanical, electrical, and software redundancy. I’m really good at it (and my employer thinks so too, and our test pilots, and our customers).
So I am qualified to have an expert opinion on the design elements of the 737 MCAS and the accidents. And my considered opinion (which is shared by my colleagues, some of whom are even more experienced than I) is that MCAS managed to cross the line between pilot assist and primary flight control, but has insufficient redundancy and insufficient automatic fault detection and isolation for primary flight control, and as such has failure modes that don’t look like a classic 737 runaway stabilizer trim, which makes them significantly harder to diagnose and do the right thing(cut out the electric trim). A good or maybe even average pilot can do that diagnosis and cut out the electric trim that is the MCAS control effector. But below average pilots find it much harder.
Part of what I really hope comes out of this are statistics from US airlines on the MCAS failure rate, because I strongly suspect that the US pilot population was encountering and properly diagnosing MCAS failures. But the US commercial airline pilot population is almost certainly in the above-average skills set, so I would expect them to not have too much difficulty with MCAS. But Third World pilots from ab initio programs…not so much. Which puts the onus on Boeing to design systems that are safe in the hands of mediocre-at-best pilots, or stop selling to customers whose pilots are firmly in the mediocrity. Any flight control engineer knows the “golden arm” test pilots aren’t the ultimate customer, and those golden arms know it too; we both know we’re responsible to deliver an airplane that can be flown safely by the masses, not just the elite.
It’s easy for a pilot without engineering experience and training to slag the pilots of these two flights as idiots, and there’s some truth in that, but Boeing’s poor design decisions played a substantial role. When I’m faced with a thorny design issue, I always ask myself, “If I were testifying at an Accident Investigation Board, could I in clear conscience say this was a good design?” If the answer is no, I find another design alternative, even if it costs more or slips schedule. In my considered opinion, nobody at Boeing can say “yes” to my thought experiment on 737 Max and MCAS.