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> I’m not sure where the idea comes from that a new type certificate or even simulator training would destroy the program.

A new type rating cannot use grandfather rights. There is plenty of stuff in this plane that is not permitted any more (like the door design over the wings). Those would be massive changes to the plane.

Source on door over wings? The brand new design A220 (Bombardier C-Series) has an over wing exit. I just couldn’t find anything in a couple of quick searches banning it.

That’s just one example though and you’re likely right. The thing is though most of these systems have modern adaptations that could be applied. They just haven’t been because of the desire to keep it a 737. They’re things that can be changed/fixed whereas the aerodynamics of the design cannot be be changed easily.

The 737 overwing exits have a non plug style door which are not permitted any more. It uses a few sensor inputs to engage a lock so you can’t open it during flight.

Do you have a source for this? From what I can find, the up-and-coming A220 has the same design[0] for the overwing exit as the 737, which was added in the 737NG redesign. Earlier 737s had plug doors: https://www.youtube.com/watch?v=2gZ22iQBlmc

0: https://rr-spotter.de/im-airbus-a220-300-von-air-baltic-nach...

Actually I misremembered. It was not the plug style that causes issues but the size of the exit. The change from the throw out door to the hinge version in the NG is apparently a change they made to satisfy JAA: https://www.flightglobal.com/news/articles/boeing-details-em...

Oddly enough that news bulletin says it's still a plug door which it clearly is not in the final design.

Overall the root cause I believe is generally weight of doors and evacuation time. I had a few conversations about this around the time the second accident happened and grandfather rights were brought up by people from the industry I talked to as an expensive problem for a new type rating.

The issue is probably the other doors. The 737 doesn't have any sort of gas assist to help in opening the main doors in an emergency.


The A220 is in service today, on Delta. I flew one this afternoon.

Today I Learned... Thanks!

The 737 Max "still" uses paper manuals for technical support and has a variety of features no longer found in modern planes.

"It is the only modern Boeing jet without an electronic alert system that explains what is malfunctioning and how to resolve it. Instead pilots have to check a manual."


This scares me far more than the MCAS issue generally to be honest. The fact that all this modern technology is being thrown out for economics and we’re basically building 50 year old planes en masse. It makes me very sad.

Oh boy... Wait till you learn about the backbone of our military air forces.

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