Watched last night a two hour doco celebrating fifty years of the all mighty Jumbo, documenting its gestation, birth, troubles, and service. One point made was the pressure by management on Joe Sutter to cut costs, but Joe resisted any attempt to short change engineering standards as he saw them, or the provision of redundancy in the systems. The company came within two months of bankruptcy.
I wonder if the company now has someone of Joe's character in the engineering able to withstand the various pressures applied by management, who rightfully are concerned with the money side of the business.
https://businessthinker.com/the-boei...etting-it-all/
An article by Macarthur Job on the O'Hare DC-10, I see parallels in system design re MAX.
DC-10 Design
Other designs include mechanical locking devices to prevent movement of slats by external loads following a system failure. This feature was not deemed necessary in the DC-10 because it was demonstrated that sufficient lateral control was available to compensate for asymmetrical conditions throughout the aircraft's flight envelope. Analysis of the takeoff regime showed that, with all engines operating, the aircraft would accelerate to and maintain a positive stall margin.
Even so, the analysis showed that if slat retraction, and a loss of engine thrust were to occur during takeoff, the aircraft's capability to accelerate to a positive stall margin would be compromised. But because mathematical probability showed this hazardous combination to be extremely unlikely, the design was accepted as complying with requirements. If the structural loss of a pylon had been included in the probability projection, the vulnerability of the hydraulic lines and slat position feedback cables might have been recognised.
Also, the result of the combined failure of the hydraulic and electrical systems was not considered. When the effects of asymmetric slat settings on controllability was first evaluated, it was presumed that other flight controls would be operable and that the slat disagreement and stall warning systems would be functioning.
In this accident however, the loss of those systems, intended to alert the crew to the need to maintain airspeed, was critical. The stall warning system lacked redundancy, there was only one stickshaker motor, and the left and right stall warning computers did nor receive crossover information from the applicable slat position sensors on opposite sides of the aircraft.
In summary, the certification of the DC-10 was carried out in accordance with the rules in effect at the time, and with then accepted engineering and aeronautical standards. In retrospect however, the regulations appeared inadequate, in that they did not require manufacturers to allow for multiple malfunctions resulting from a single failure, even though that failure was extremely improbable.
McDonnell Douglas considered the likelihood of the structural failure of a pylon and engine to be of the same magnitude as a failure of a tailplane or wing. The pylon structure was therefore designed to meet and exceed all foreseeable loads in the life of the aircraft.