[Imp]

It is possible but improbable Pat you may get lucky but I would allow for using 3 or 4 demo charges before it drops. As said use the Z key but you need a good die roll to pull it off.

This is actually pretty realistic bridges are hard to drop, the charge needs to be placed so it effects the supporting structure to have any real effect.
"Wooden" bridges in this game are sturdy affairs they can support a tank after all.