FAA didn’t learn of 737 Max safety review until after crash

In the months after Boeing started delivering its new 737 Max jets in 2017, the company’s engineers discovered a problem: One of Boeing’s suppliers delivered flight control software that did not meet its requirements, Boeing disclosed Sunday.

It wasn’t until after a deadly plane crash involving related flight control software that the company informed regulators about the issue, which safety review committees from Boeing and the FAA determined was a “low-risk” problem, according to a statement on Boeing’s website.

The admission comes at a time when Boeing and the FAA face tremendous scrutiny over whether design flaws could have contributed to the deaths of hundreds of people in Indonesia and Ethiopia, where two 737 Max jets crashed in recent months under similar circumstances.

The disclosure also could feed into a broader inquiry over whether the process for designing and certifying commercial jets in the United States is flawed.

The 737 Max was grounded worldwide in midMarch after the second crash brought the death toll to 346. The software, which connects the airplane’s external sensors to pilots’ cockpit displays, is designed to alert pilots when sensors on either side of the plane are reporting conflicting measurements for the plane’s “angle of attack,” a measure of how the plane approaches oncoming wind. Boeing included the alert as an optional feature in the 737 Max to alert pilots to potential equipment failures.

In its statement, Boeing said the planes can be operated safely without the alert.

“Neither the angle of attack indicator nor the AOA Disagree alert are necessary for the safe operation of the airplane,” the statement read. “They provide supplemental information only, and have never been considered safety features on commercial jet transport airplanes.”

Boeing’s statement comes a week after The Wall Street Journal reported that the angle-of-attack disagree alert was inoperable when Southwest Airlines and other carriers started flying the planes.

“The disagree alert was not operable on all airplanes because the feature was not activated as intended,” Boeing said.

When it discovered the software problem in 2017, Boeing assigned a committee to review the issue, which ultimately determined that the planes were safe to fly. But it wasn’t until last November, after the Indonesian plane crash, that the company informed regulators at the Federal Aviation Administration.