The Ethiopian MAX 8 of the sort that crashed earlier this year. No one in his or her right mind should be pining for this monstrosity to get back in the air anytime soon.
"I'd walk before I'd get on a 737 Max." - Sen. John Tester in Senate hearing yesterday on Boeing's 737 Max
"In the now infamous debacle of the Boeing 737 MAX, the company produced a plane outfitted with a half-assed bit of software programmed to override all pilot input, and nosedive when a little vane on the side of the fuselage told it the nose was pitching up." - Maureen Tkacik, 'How Boeing's Managerial Revolution Created The 737 Max Disaster', The New Republic, October, p. 12.
The interrogation of Boeing CEO Dennis Mullenburg yesterday was notable for one thing: the consistency of weasel words and lack of transparency as to the basis for Boeing's two 737 MAX -8 crashes. In effect, no one watching would gain any deep insights. Not like they would if they took the time to read the 12-page article in The New Republic by Maureen Tkacik. Given most readers might not have ready access, I provide the link to this must read article here:
https://newrepublic.com/article/154944/boeing-737-max-investigation-indonesia-lion-air-ethiopian-airlines-managerial-revolution
Given the length of the piece, I summarize below what I believe are the key takeaways:
- Boeing's acquisition of McDonnell Douglas in 1997 foreshadowed its downward spiral in terms of the quality of decision making, and becoming hostage to Wall Street shareholder imperatives. Thereby Boeing adopted the "Hollywood model" for dealing with engineers: Hire them for a few months with project deadlines approaching then fire them "when you need to make numbers"
In other words eliminate engineers' input to expedite a product goal, given it likely means cutting corners to appease Wall Street leading to "endless wars" with assorted unions, including mechanics.
Examples:
Much of the software on the MAX had been engineered by recent grads of Indian coding schools, who earned barely $9 an hour. Boeing didn't want to pay any more.
In a number of cases quality control documents were regularly forged
Employees who tried to enforce standards were sabotaged
Planes were regularly delivered to airlines with loose screws, scratched windows and random debris everywhere.
- The 737 Max's design was so far out of whack with aerodynamic principles that even test models in wind tunnels "botched certain extreme maneuvers."
At the core of the issues were the use of two, massive "LEAP" engines manufactured by CFM (a joint 50-50 venture of GE and the French firm, Safran). The massive engines' fans were over 40 percent larger in diameter than the original 737 Pratt & Whitneys - and weighed in at twice the weight of those original engines. The correction for the increased weight was translated into a longer and heavier fuselage and also a wider wingspan. But the key bugbear in altered design was the inability to increase the plane's height. (Which would have meant redesigning the landing gear and risking an easier FAA certification.)
The aerodynamics were negatively impacted because the LEAP engines were too large to just tuck into their original positions underneath the wings so Boeing's engineers decided to mount them slightly forward - just in front of the wings. The problem was that this change caused the plane's center of gravity to also move forward given the engines' mass.
The alteration using a MAX replica the size of an eagle - with tests in a wind tunnel - disclosed even 4 years before certification that the plane was a mess. The aerodynamic profile caused the tail to keep pitching down while the nose pitched up. There was no normal way to alter the aerodynamics to get it to fly so the engineers devised the MCAS software fix to do the job. The problem was the software pushed the nose down in the event of rare set of circumstances in conjunction with the "speed trim system". (Devised in the 1980s to smooth takeoffs).
Once the MAX "materialized" in actual scale 4 years later test pilots discovered how it was even more stall prone than its predecessors. This led Boeing to modify the MCAS to force down the nose of the plane whenever the angle of attack (AOA) sensor detected a stall - and regardless of the speed. The trouble was Boeing created an additional problem to solve the original problem of unstable aerodynamic design.
In this case, Boeing had to give the MCAS system more power while it removed a safeguard - but not in a formal, specifically documented way that might have given the FAA pause in any certification. The issue is traced to the fact that while the MAX has two AOA sensors only one was programmed to trigger the MCAS. One Boeing whistleblower quoted in the NR article gave a simple explanation: if a program required data from BOTH sensors it would have had to account for any divergence. Also the possibility that any sensor disagreement would trigger a cockpit alert. That in turn would require additional and more complex training (D level) and no Boeing hotshot - least of all Mullenberg - wanted to risk that in a race to beat Airbus in gaining market share.
Therefore, Boeing's machinations spawned the single point of failure; the MCAS system was programmed to turn the nose down based on the feedback from a single sensor. In other words, they'd created the "world's first self -hijacking plane."
Worse, the single system programming was such that it enabled the plane to nose dive again 5 seconds later, and "again five seconds after that ad infinitum".
- The worst travesty is that Boeing kept the details of the MCAS software fix and actions hidden including from test pilots.
Thus,
Pilots were particularly stunned (e.g. at the Lion Air Crash last year) and the tracing to the MCAS given MCAS "had been a big secret, largely kept from Boeing's own test pilots, mentioned only once in the glossary of the plane's 1,600 page manual and left entirely out of the 56 minute Ipad refresher course that some 737 pilots took for MAX certification."
And to top it off, "most pilots only heard of the MCAS from their unions which had gotten wind of the software from a supplementary Bulletin Boeing put out."
Outraged, many pilots took to message boards and others contacted the press including Dominic Gates of The Seattle Times, Sean Broderick of Aviation Week and the WSJ's Andy Pasztor. Subsequent investigation has uncovered Boeing lobbied (FAA) regulators successfully to keep any explanation of the system from pilot manuals and training - then after the 2 crashes tried to blame the foreign pilots for improper or inadequate training. We now know this was a ruse and depraved way to shift blame when Boeing alone bears responsibility for designing an unstable plane and a god-awful attempt at a software fix which they were ashamed to even admit existed..
Other pilots went to their corporate management to try to get additional resources "to train people on the scary new planes."
In the end not enough was done and neither the Lion Air or Ethiopian Airlines pilots had a chance, see e.g.
BOEING 737 MAX 8 May Not Fly Until 2022 - If Then ...
The bottom line is that this plane is an aerodynamic disaster - and was from the instant the massive LEAP engines were mounted so far forward so that no natural re-design (that cost less than projected) was possible, or recertification without complications. It is a menace to fly, for any passengers and Sen. John Tester was correct to express misgivings. I would not go so far as to "walk" instead of flying, but I would take a train.
Nobody in his or her right mind ought to be cheering for this aerodynamic monstrosity to take to the skies again, if ever. Not unless and until the entire plane is redesigned without the need for an MCAS "fix" to hide in the background ready to "self hijack".
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