الجمعة، 13 ديسمبر 2019

The FAA Knew the 737 MAX Was Dangerous and Kept It Flying Anyway

Boeing 737-MAX9 Artwork K65780. Credit: Boeing

One of the major questions in the wake of the 737 MAX’s two crashes was how much the FAA and Boeing knew about potential problems with the aircraft. Months of investigation into the 737 MAX have painted an ugly story of how Boeing outsourced critical production in a bid to cut costs. The long-term decline of the company’s engineering culture has been covered at length, as has the FAA decision to allow Boeing to self-certify its aircraft.

It turns out the FAA was fully aware that the 737 MAX had a much higher likelihood of crashing than any other aircraft manufactured today and signed off on the plane anyway, the Wall Street Journal reports. After the Lion Air crash in Indonesia, the FAA conducted a review of the 737 MAX and estimated that the jet would suffer a fatal crash every three years over its expected 45-year operating lifetime.

How does that compare to the safety record of other airliners? Here’s the WSJ:

The projected crash total, according to the Journal’s analysis, was roughly comparable to all fatal passenger accidents over the previous three decades—from any cause—involving Boeing’s 757, 767, 777, 787 and the latest 747 models combined. The MAX fleet was eventually anticipated to be nearly 5,000 jets world-wide, while the other fleets together total slightly more than 3,800 aircraft.

According to the FAA, in other words, the risk of dying on a 737 MAX over its lifetime was equivalent to the combined historical risk of dying on five other aircraft, many of which operated at a time when the number of aircraft crashes per year was higher. Rather than pulling the aircraft and repairing the MCAS system’s known deficiencies, Boeing and the FAA decided on a flawed strategy of reiterating education on MCAS recovery techniques in the short-term. Long-term, Boeing was supposed to provide a software solution that tweaked MCAS performance. The FAA decided that doubling down on pilot messaging and the eventual software update would address the problems and allow the aircraft to keep flying.

PK-LQP, the aircraft involved photographed in September 2018, six weeks before the accident

The 737 MAX’s safety record during the time it operated amounted to two catastrophic accidents for every million flights. The previous generation of 737s logged one catastrophic accident per 10 million flights. The global accident rate for all Western-built jets in 2018 was one fatal crash per three million flights. The 737 Max’s ratio does not reflect well on Boeing or the FAA and according to the WSJ, the accident rate on the 737 MAX after just Lion Air should have been an immediate red flag. These values are far higher than what the agency is supposed to permit. According to the FAA’s analysis in December 2018, “risk is sufficiently low to allow continued growth of the fleet and operations until the changes to the system are retrofitted.”

Talk about a prediction that didn’t age well. The Seattle Times notes:

In separate testimony, former FAA engineer Michael Collins recounted how at least 18 experts within the safety agency all concurred that Boeing should be required to modify the 1960s-era design of the MAX’s rudder cables to meet current regulations — only to be stymied by an FAA manager… as certification of the MAX loomed and Boeing hadn’t changed the design, the head of the FAA’s Seattle-based Transport Airplane Directorate, Jeff Duven, overruled his own technical specialists and approved the unmodified Boeing design.

The rudder issue is a separate problem from MCAS, but the fact that the FAA was willing to overrule 18 separate experts who collectively recommended a change is worth investigating given the overall state of the 737 MAX.

The 737 Max is expected to return to service in Q1 of 2020, but the date has been repeatedly pushed back. It’s not known if the aircraft will actually be ready to meet its Q1 2020 reintroduction. The FAA analysis document, dated 12/3/2018, can be found here. The question of why the FAA repeatedly overruled its own specialists in deference to Boeing is also under investigation.

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