"It may even be that 737 MAX has “inherited” some certs from its “predecessors” (same airframe?)..."
Boeing has relied on Grandfather Rights for the 737-Max and earlier developments. The fundamental certification for the 737-Max dates back to the original certification issued in 1967. That's a 50 year old certificate of airworthiness being applied to a plane that is fundamentally different to that originally certified by an FAA that is today effectively a different organisation. All in the interests of saving money.
Biting the hand that feeds IT
