Once, when in feeders. Rookie, over 30 yrs ago.
Hooked up my own set. Had to take two-lane for about 200 miles, one way. Went over ROUGH, I mean, ROUGH, bridge going out of town. Back trailer locked up, smoke billowing like a tire fire, air pressure dropping. At crest of bridge (yeah, up and down, over RR tracks), got out, went to middle, found out the service line from back of front trailer popped off dolly service hookup. Whew! That's all? Hooked it back up. Life is good. Wait, not so fast!
Set starts rolling DOWNHILL now, without ME in it. Like the true veteran I was (sarcasm intended) I ran after the cab as it was heading toward concrete wall. JUMPED up on steps of old 21000 series friend-Model Mack and popped tractor brake that I, conveniently forgot to pull...SINCE I WAS STOPPED ALREADY!
Why didn't I just, quickly pull service line back off, stopping set, or turn valve off, if I would have been able too? I dunno.
OK, made it, but just barely. Never did that again. On ANY terrain. ALWAYS popped cab brake for WHATEVER reason.