Southampton, on England's south coast, is the final home of what was once the biggest hovercraft ever built - the Princess Margaret. As crews strip it down, Zdenek uncovers the principles that allow this 300-ton amphibious craft to hover weightlessly over the ground - and the water. Zdenek explores how the era of mighty passenger hovercrafts was finally brought to a surprising end by cheap alcohol - and then joins the crew of an LCAC, the U.S. Navy's state of the art military hovercraft, deployed in some of the world's most extreme conditions.

• Chad Zdenek