737 MAX sales will recover but another crash like DC-10 could be…

Boeing 737 MAX deliveries will surely regain momentum, though it may take time to get approvals from the various regulatory authorities now that the FAA has lost its sheen.

Airlines, in particular low-cost-carriers, have put so much investment in the 737 and are not in the main going to move to Airbus, even though they may suggest the possibility to get better terms from Boeing. In fact, Airbus would not be able to ramp up production very significantly.

Parallels with the DC-10

However, there are some parallels with the sad history of the McDonnell Douglas DC-10. Design was rushed in order to compete with the Lockheed’s L1011 TriStar.

In 1972, a DC-10 flying along the border between the US and Canada almost crashed when it became almost uncontrollable when a cargo hold door blew out with the result that the pressure differential between the passenger cabin and the hold caused the cabin floor to buckle.

The hydraulic lines and cables to the tail were attached to the underside and damage to these was what was making the aircraft difficult to control. Fortunately the floor had been reinforced to support a piano for an inaugural event and the pilots were left with just enough control to bring the aircraft back to the airport with good airmanship, adjusting the power of the low-slung engines to raise and lower the nose.

Within three weeks of the Detroit/Windsor scare, the NTSB made two urgent recommendations:

1.   Modification of the DC-10 door-locking mechanism so that it is physically impossible to bring the vent-flap-locking handle to its stowed position without the C-latch locking pins being fully engaged.

2.   Vents (holes) should be incorporated in cabin floors to greatly relieve sudden pressure differentials, such as those caused by the opening of a cargo hold door in flight.

The Gentleman’s Agreement

The NTSB could only advise. It was up to the FAA to make these two modifications mandatory.

Just when the FAA was about to issue an airworthiness directive (AD) making interim and long-term solutions mandatory for all US operators of the DC-10 (which foreign operators would have followed), discussions between the FAA administrator and the president of the Douglas division of McDonnell Douglas led to the senior FAA technical staff being overruled. Douglas and the FAA were no doubt being subjected to pleading from US airlines, who would not want to take their aircraft out of service in the peak summer season. So, the FAA did not issue that airworthiness directive. Instead, McDonnell Douglas almost immediately issued recommendations, in particular the installation of a “lock mechanism viewing window.”

This gentleman’s agreement between the FAA administrator and McDonnell Douglas’s Douglas division president sufficed to prevent a repeat accident in the United States, but not to prevent a DC-10 crashing after taking off from Paris for London with the loss of 345 lives.

The FAA hurriedly made the measures the NTSB had recommended mandatory. These included floor vents. Passengers are safer now thanks to that.

The DC-10 was only grounded when a DC-10 taking off from Chicago lost an engine and crashed.

Further to this, the public lost confidence in the DC-10 and sales petered out. This was unfair as the engine had fallen off because maintenance workers had contrary to instructions used a fork lift to remove the engine and in so doing had damage the pylon. In fact, the DC-10 albeit in limited numbers flew safely for airlines for many years.

If the max were to similarly have a terrible accident in the US sometime in the future, one that was not Boeing’s fault, the public’s refusal to fly on it could, however unfairly, be a serious problem for Boeing and not least those low-cost-carriers.

SEE CHAPTER 6 in Table of Contents

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