That's impossible. Edit: As CoreDog said, it would be a cost nightmare. Already airlines would suffer massively if any type is grounded. Ground 737s or A321s?

That's impossible. Edit: As CoreDog said, it would be a cost nightmare. Already airlines would suffer massively if any type is grounded. Ground 737s or A321s? It would be like 9-11 all over again, shut down most every flight of almost every airline. Even grounding a specific version of a type, like 737-700 would be difficult to handle for the airlines that fly them. Alaska would have to cancel nearly 10% of their flights. And it's hard to imagine how the FAA could ground the 737-700 and not the 737-800 at the same time given they are almost identical, which would ground 2/3s of Alaska's fleet. Airlines can consolidate their fleets around a few specific models because it's super cost effective, and the chances of grounding any single model are virtually nil. 737s and A3xx have flown many billions of miles safely since their last incident, it's almost impossible to imagine a problems so urgent and dangerous it would require grounding an entire fleet of planes that flies safely every single day.