U.S. Aviation Administration Orders Airlines to Inspect Thousands of Boeing 737 Jets Due to Fear of Switch Failures

U.S. Aviation Administration Orders Airlines to Inspect Thousands of Boeing 737 Jets Due to Fear of Switch Failures
A Boeing factory worker working outside the cockpit of a 737 Max 8 under production at the company's Renton, Washington plant in March 2019. (Photo: Stephen Brashear, Getty Images)

Boeing’s had a rough go of it lately: After two crashes of its 737 Max jetliners in 2018 and 2019 resulted in a cumulative 346 deaths, the entire line was grounded for months and subsequent investigations showed the manufacturer rushed out the craft with shoddy software and without sufficient oversight from industry-friendly regulators. Now the U.S. Federal Aviation Administration (FAA) has ordered unrelated, but urgent, inspections of thousands of Boeing planes.

According to Reuters, the FAA directed all operators of Boeing 737 series aircraft to carry out repeated inspections of cabin altitude pressure switches, which help ensure that planes remain properly pressurised during flight. Failure of the switches (two of which are in each plane for redundancy purposes) could result in the incapacitation of pilots, flight crew, or passengers.

The order applies to 2,502 aeroplanes registered in the U.S. and is likely to impact another 9,315 across the globe. While the FAA does not have legal authority over planes flown exclusively outside the U.S., Bloomberg reported, it’s fairly certain that foreign regulators will issue similar orders or that foreign 737 operators will carry out such inspections even if they’re not legally mandated.

According to Reuters, the inspection order follows reports in September 2020 by one operator that the switches failed on three different 737 models of aircraft, although the FAA didn’t indicate in its order that there were any reports the failures occurred in the middle of a flight. The news agency wrote that after the initial report, Boeing conducted its own investigation and determined there was no issue.

But the FAA and Boeing revisited the matter and determined in May 2021 that “the failure rate of both switches is much higher than initially estimated, and therefore does pose a safety issue.” The FAA wrote it “does not yet have sufficient information to determine what has caused this unexpectedly high failure rate,” Reuters added.

The tests must be carried out within 2,000 flight hours of the last test of the switches, before 2,000 flight hours since the issue was ordered, or within 90 days, whichever comes first.

“Safety is our highest priority and we fully support the FAA’s direction, which makes mandatory the inspection interval that we issued to the fleet in June,” Boeing wrote in a statement to news outlets.