I guess a dead man switch in the tower would have been too complicated.
A loud horn sounds if a reset switch isn’t flipped every 3 minutes or when a light comes on at random. I think trains use something like that for operators. Much cheaper system than more personnel. Or connect the horn to the radio as the lights at many airports are and have the pilot sound the horn by keying his radio if the tower radio hasn’t been keyed in 2 minutes.
I actually LIKE that idea!
Right or wrong having two people in the tower does not bother me. I travel by air quite a lot and hearing all these mistakes due to complete laziness is a bit concerning.
This is all based on the theory that one will stay awake though.
I am all for hooking them up with “Pulse Monitors” to measure their pulse. Slows down when relaxed or sleeping. Sound an air-horn.
Or meth.