[progbits]

> because automatically restarting a transmitter in an unmanned tunnel is not an acceptable failure mode

Why?

Also, surely they don't mean unmanned, who is listening to the AM emergency broadcast then?

[nomel]

I would assume because restarting would be saying "it's ok if the control system in our emergency transmitter sometimes fails, so let's just pretend it didn't happen and ignore it! yolo!".

I think a reasonable approach would be to have a redundant system, that gets activated if failure occurs in the first, and blasts a full alarm message to "abandon the tunnels, emergency system has failed!" type message.

[rlpb]

If the emergency broadcast system fails, perhaps they need all the radio channels they use not to be jammed?