Septic HISS, Bridge-layer

Why did the HISS cross the bridge? Obviously to get to the other side, but where did the bridge come from? It came from this little pioneer number of course. Everything for engineers on the go - mines, mine detectors, chainsaws, and an expandable bridge. Finally your techno vipers can use those hydraulic packs for something worthwhile - laying bridges. Oh, don't forget the shovels and barbed wire - after all, what self respecting engineer doesn't have barbed wire???