Crossing a bridge three abreast at night

Five people must cross a bridge in the dark with a single torch. This bridge is sturdier than most: it holds up to three people at once. As always, every crossing needs the torch, so someone must walk it back, and a group crosses at the pace of its slowest member.

The five solo times are 1, 2, 4, 6, and 9 minutes.

What is the fastest way to get all five across, and how long does it take?