In the days since the horrific Ethiopian Airlines crash, I have received a lot of email from pilots, aircraft engineers, and others with experience in aviation. These have been in response to three previous posts: first here, then here, then most recently here (with quotes from pilots’ observations about the Boeing 737 Max via NASA’s Aviation Safety Reporting System).

While I sift through the other messages, let me start with one from a highly experienced pilot and flight instructor. His name is Wally Magathan, and he has worked as an airline pilot, an Air Force pilot and C-5 Galaxy flight instructor, and an instructor in airline L-1011 flight-simulators. I know him through COPA, the organization of pilots and owners of Cirrus’s small single-engine airplanes.

With Magathan’s permission, I quote a post from him, offering a professional’s view of risk-management after these two Boeing 737 Max tragedies.

(For brief background, and as a reminder: the Boeing 737 Max has different handling characteristics from previous 737 models, because its engines are in a different place on the wings. This new engine placement increased the tendency of the plane to “pitch up”—that is, to point its nose upward, in a way that could increase the risk of aerodynamic stall. The MCAS system was added to offset this tendency, when detected and when the plane was being hand-flown, by automatically pointing the nose back down. The main hypothesis about last fall’s Lion Air crash, in Indonesia, is that this MCAS system went out of control, because of a failed sensor reading, and pushed the nose down, down, down, until the plane plunged into the sea. The main question after that crash was whether the Lion Air pilots had been appropriately informed about how MCAS worked, and trained on how to turn it off. No one yet is sure whether the same problem was part of the recent Ethiopian Airlines crash.)

Magathan says this about training, design flaws, and who should be grounded, when:

-Boeing’s design deficiency [JF note: having the MCAS rely on a single data source, the “angle of attack” indicator, without backup or comparative sensors] sets up the need for pilot training on how to overcome it. -Boeing’s failure to highlight the change resulted in no specific MCAS pilot training. Those two big mistakes, it now appears, likely caused two tragic major catastrophes. Shame on Boeing if the final analysis bears these points out. The corrective action is simple and within the capabilities of any competent airline captain to execute. Certainly easier than dealing with an engine fire or loss of multiple hydraulic systems. There is a broad spectrum of abilities in any group of pilots, and without an emphasis training, some of them will be unable to overcome the design deficiency, even if the emergency procedure is simple to carry out. All the lights and buzzers going off will freeze the less capable pilot who has not been trained to drill down to what is going on, and to flip the switch. Training has to be to the lowest level of ability, if you’re operating an airline with any significant number of pilots. They all can't be Sully Sullenbergers. To me, from the standpoint of an airline pilot, there was no need to ground the fleet. Just ground each and every 737MAX pilot until he or she has been trained on the MCAS. After two accidents, require a week in the simulator—for overkill to make sure it penetrates even the dimmest bulbs. But nobody flies again until they have it. In effect that grounds the fleet, but only so long as the training takes. At the same time, regulatory bodies can require Boeing to eliminate the design deficiency so that the training on the MCAS need not be so intense, a process that could take months if not years. But if I were speaking as a non-flying member of the public, and as a politician who must answer to them, I would say: ground the fleet now. As far as the public is concerned, the industry had its chance and blew it. I would have no confidence in the plane nor the industry until an explanation is found and the design changed. Nor would I buy a ticket on such a plane. Once the public pressure became too great, the grounding of the fleet was inevitable—but not because the plane is unsafe when flown by a properly trained crew. Boeing will pay a price for this, if the final analysis holds these accidents would not have occurred in a 737 model that had no MCAS.

Obviously (as I know from the inbox) other pilots and engineers have a range of views. But I thought this was a particularly lucid description of the relationship between technology and training, and about the difference between views from inside the industry and reactions from outside.

Please read on for another message from another airline pilot, which has just come in.