[StopHammoTime]

Type ratings are not prohibitive to achieve once a pilot has achieved an ATPL. It’s about 5-6 weeks per pilot. Yeah, it’s a pain but it’s also not a devastating road block. Ironically if you hear some airlines talk about the whole point of MCAS and no extra type rating requirement didn’t actually factor in as much as Boeing thought. Training and aircraft expense is actual minor compared to fuel efficiency and availability of aircraft. If you’re running 20 year old 737NGs the new engines on the MAX are going to save a tonne of money, even after potential reputations damage. It’s all risk management.

Edit: in regards to maintenance a lot of airlines are outsourcing maintenance to bigger providers so that’s less of a deal than you’d think as well. Fuel really is one of the largest factors in this and an extra 5 years of expensive gas while waiting for a new plane may be too much for budgets to bear.

[danpalmer]

Thanks, that's interesting to know about the outsourced maintenance, that does make sense and would certainly increase that flexibility.

Re: pilot training. I could imagine that going from a 737 to a 787 would be substantially easier than from 737 to A320, due to standardisation in interfaces, processes, documentation, etc, within one manufacturer. Is that the case? 5-6 weeks does still seem like a lot of downtime for a commercial pilot, and rolling everyone through that sounds like it would be prohibitively difficult for many airlines. Plus my understanding is that it's sort of a one way street, pilots don't typically (or can't feasibly?) stay rated for two aircraft types for long periods, so it would still reduce flexibility if an airline split its fleet right?

[WalterBright]

The 757 and 767 are quite different airplanes, but they were designed to minimize the differences as the pilot sees them. This increases safety by pilots not getting confused about which airplane they are driving in a crisis.