The 737 MAX Debacle is Driven by Profits Trumping Safety

It turns out that the predecessor system for MCAS, which was used on Boeing’s military tankers, was both less aggressive, and easier for the pilots to override.

So, why did Boeing create the clusterf%$# that crashed two planes?

The obvious answer is that Boeing has sold the MAX on not requiring pilot recertification, which is not an issue in the military market.

This was a deliberate choice by the suits:

Boeing Co. engineers working on a flight-control system for the 737 MAX omitted key safeguards that had been included in an earlier version of the same system used on a military tanker jet, people familiar with the matter said.

Accident investigators have implicated the system, known as MCAS, in two deadly crashes of the jetliner that killed a total of 346 people.

The engineers who created MCAS more than a decade ago for the military refueling plane designed the system to rely on inputs from multiple sensors and with limited power to move the tanker’s nose—which one person familiar with the design described as deliberate checks against the system acting erroneously or causing a pilot to lose control.

“It was a choice,” this person said. “You don’t want the solution to be worse than the initial problem.”

The MAX’s version of MCAS, however, relied on input from just one of the plane’s two sensors that measure the angle of the plane’s nose. The system also proved tougher for pilots to override. Investigators have implicated the system in the fatal nosedives of a Lion Air jet in October 2018 and of an Ethiopian Airlines MAX in March. Indonesia is expected to fault that MCAS design, in addition to U.S. oversight lapses and pilot missteps, in its final report on the Lion Air crash into the Java Sea, The Wall Street Journal has reported.

Now, Boeing’s expected fix for the 737 MAX will make its MCAS more like the one used in the tanker, according to people familiar with the matter.


Boeing developed the MCAS for the military tanker around the early 2000s, another person familiar with the project said. The tanker was a military derivative of Boeing’s wide-body 767 commercial jet and included pods on its wings used for air-to-air refueling of fighters and other war planes. Those wing pods added lift and caused the tanker’s nose to pitch up in some flight conditions, risking the plane’s ability to meet Federal Aviation Administration safety requirements, people familiar with the matter said. So engineers devised MCAS software, which automatically pushes down the tanker’s nose if necessary, to comply with FAA standards, these people said.

In a key difference from the subsequent version of the system used on the MAX, the system on the tanker moves the plane’s horizontal stabilizer—the control surface perpendicular to the airplane’s tail—once per activation and not repeatedly, the person familiar with the tanker project said.

The tanker engineers also gave the system only limited power to nudge the plane’s nose down to ensure that pilots would be able to recover if it accidentally pushed the plane into a dive, said the person familiar with the tanker’s MCAS design. That meant MCAS had little authority over the stabilizer, which made it much easier for pilots to counteract.

The question raised is, “Why the disastrous changes in the system?”

This was keeping retraining to a minimum, and it killed people.

One comment

  1. Quasit says:

    The worst of it is that the people who are responsible for all of those deaths – and I'm not just talking in this specific incidence – will never even be charged for their crimes, much less punished. They will live the rest of their lives in privilege, comfort, and praise.

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