https://www.euronews.com/2019/03/12/caa-suspends-boeing-737-...

http://publicapps.caa.co.uk/docs/33/SD2019001.pdf

Norwegian Air and Norwegian authorities had the same information (or indeed lack thereof), but did not act until now. Given the known similarities, and the lack of data that rules out a problem with the B737 MAX, the responsible thing is to err on the side of caution.

People are pattern-matchers, and if 99% of flying the plane is the same except the part that will kill you if you don't do it the new way--well, people will do it the old way and die. That's infinitely more true in an emergency situation where you tend to fall back strictly on training and instinct.

If you want to jar people into different behavior, the interface needs to be different as well. Otherwise it looks like the same old contract.

I think many of us kind of know this from GUI/API/whatever design, but there's no reason jet planes would be any different.

Considering that pretty much any criticism can be dismissed with "better safe than sorry, also everyone else was doing it, we had to consider the optics" it makes perfect sense to step in line and ground them like everyone else. Not doing so would just be stupid when there's near zero downside to the people making the call.

It's like highway traffic. Sure you can obey the letter of the law but when everyone else is doing something drastically different your exposure to risk is minimized if you just do what they do whether it's right or wrong.