It is self service baggage handling. They don't have the staff to move all those bags.

And the belly of the plane is not big enough to hold it all. We would require a whole new civil fleet to make that a reality.

Further they would just have to spend more time looking at checked baggage that can be controlled with timers and remote controls meaning the same if not longer delays. You would just be required to get your bags there earlier.

Lastly from a tactical point of view we want carry ons. If the bad guys are required to put nefarious devices in checked bags they will be harder to find.

I don't know the magic solution but this proposal is just not practical.

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