Tis funny, I was repairing the bridge and one of my TM8’s were hangin out under the bridge… As I completed the repair, the bridge goes up and my m8 was Tkilled. LOL! Is that normal? Something that we need to be aware of during construction?
Eng Says: I'm Repairing the bridge.. All Clear! I Hope..
The person who is near a construction gets a warning like this - leave construction area. Otherwise they go POP
I have always wondered this myself. I have alwasy assumed that when the bridge is complete that the tank automatically starts to move across and that the dynamite dosnt go off fast enough for that to happen. Dont know for sure just guessing 
I’ve also noticed if your an Engineer, and build the footbridge from the
wrong side, when it is constructed, you get gibbed, MOD says by rubble 
Made me jump out of my skin when it first happened !! lol
Hewster
I think when you plant on the bridge it doesnt actually get destroyed until the tank moves off it. Also, I think if you panz the tank while its on the bridge, it doesnt change to “damaged” until it has finished moving off the bridge.
Better that than the tank ending up on the ice; unless youre axis anyway 
this will also happen when axis build the side MG. if a player is standing in the place where the tower is created, they get gibbed (but apparently, they dont get any warning?)