In the United States Air Force, I worked as an Airborne Command Post Communications Equipment Repairmen on the EC-135C’s and E-4A’s & B’s.
Concerning the Flash and Flash Override circuits:
From what I remember, 1) The President had Flash Override capabilities, 2)The Secretary of Defense had ‘em, 3) the Chairman of the Joint Chiefs of Staff had ‘em, and, 4) all the Commanders of the Unified Commands had ‘em.
Subsequently, because we had the Prez and Unified Command commanders flying around with us every so often, and, because we could bypass the ground equipment down in the silos and launch nuclear warheads at the turn of a couple keys without the help of anyone down in the silos, I can assure you that the Flash and Flash Override circuits worked quite well on the EC-135C’s and E-4’s!
In fact, once the “butter bars” figured out that they could drop everyone off the trunk circuits with the Flash and Flash Override buttons while we were in flight, there was no end to their mischief.
So, we started telling everyone that, per order such-and-such, section such-and-such, the Flash and Flash Override circuits had been reconfigured—like the hotline phones—to directly call the President and Vice President on their “Red Phones.”
Yup, that put an end to the butter bars’ inflight games. (Well, it put an end to THAT particular game, I should say; they had plenty of other “sillinesses” to keep themselves amused).
Anyway... Where was I, now? Oh, yeah: Heck, we even had the Full Birds scared to death that they might accidentally slip while dialing during some turbulence, hit the Flash Override button, wake up Reagan, and find themselves shipped out to Antarctica, or Bumfrumptegypt, or someplace like that. LOL!
Good times.
Cheers!