Boeing 737 chief engineer: "We don’t need fly by wire"[1]. So they put an electrohydrolical augmented mechanical system. That can be turned off. And that has a mind of its own due to MCAS.
9 years later, flight ET302's MCAS went haywire. So the crew shut off the electromechanical system which also shut off the MCAS. Which made the trim adjustment stuck inoperable due to lack of assists. So they turned it back on hoping to fix it, and crashed.
https://web.archive.org/web/20180121035035/http://blog.seattlepi.com/aerospace/2010/10/27/boeing-737-chief-engineer-we-dont-need-fly-by-wire/
All modern planes except the 737 MAX have a normal fly-by-wire with adjustable levels of computer assistance. Why was a plane made with actual ropes running down the fuselage connecting components in this day and age?
Because Boeing never modernized the 50 year old 737. Because airlines didn't want to retrain their flight crew.
Even banks had to modernize their COBOL code to handle operations outside of business hours and instant transfers.
That airplane should be taken out of service IMO.
Another quote from the chief engineer: "You can put fly-by-wire on the airplane, but is it going to buy you anything in terms of dispatch reliability? We have a very reliable flight control system on this airplane today. It doesn’t have problems.
Our friends in Toulouse like to talk about, they have a central maintenance computer. And I say, well that’s great, but you don’t need it if the plane never breaks down. It’s just a lead weight.".
