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Huge new airships for US Army: designed in Blighty
Hybrid dyno/hover vessels to make 3-week flights
High spy ship hopes to rise above enemy ground fire
In the end the Walrus was cancelled in 2006, perhaps sensibly enough as its military usefulness was rather doubtful. It was only spec'd for 10,000 feet cruising altitude, meaning that the huge craft could be attacked by shoulder-launched missiles at any point on its flight path.
Following the demise of Walrus, the only game in airship town became the US Army's Space and Missile Defence Command, interested in airships as airborne listening, communications and radar posts rather than transports. An airship can potentially stay up for much longer than a fixed-wing craft, so lowering costs and increasing coverage. The US Air Force, much preferring jets or satellites, was uninterested; but the soldiers, seeing the airship merely as a tool rather than a way of life, thought it might be of use.
Thus was born the LEMV, under which a much smaller Walrus would carry a much smaller surveillance payload on higher patrols at 20,000 feet where it would be less easily attacked by basic groundbased weapons. Risk would be further reduced by the fact that the ship would be unmanned on operations, though flown by onboard pilots when in controlled US airspace or en route to or from the warzone.
Some analysts consider that an airship-borne persistent spy package would be able to create a huge hi-res moving picture of an area - say, around a city - sufficiently comprehensive to more or less eliminate the threat from roadside bombs or insurgent ambushers. Every time such an incident occurred, it would be possible to rewind and zoom the picture so as to backtrack the bomb-placing team or whoever to their bases.
Whether such airborne spy equipment actually exists is a moot point: most of the publicly known programmes don't offer this level of capability, rather seeking to provide multiple "drinking-straw" narrow viewpoints in place of the single camera system found on most present-day surveillance birds.
In any case, the actual payload of the LEMV is to be a moveable feast: it will be built with the ability to swap "plug and play" modules in and out while deployed in theatre, so that local commanders can send it up carrying whatever they like.
The optionally manned LEMV is expected to be approximately 300 feet long and will use turbodiesels to drive its swivelling propulsors during takeoff and landing. Once on station these will shut down in favour of a more economical electric drive running from a central generator, which will also supply juice for the payload. The margin of weight supported initially by thrust/dynamic lift will mean that the ship can burn up its fuel without becoming positively buoyant, and so will not need to vent costly helium in order to land.
The ship is to fly for the first time next year, and set for operational testing shortly thereafter.
All in all, the LEMV isn't a Walrus, isn't a proper return by true successors of the great 1930s dirigibles. Nonetheless it's a very noteworthy project which could lead to great things if it succeeds: and $517m, for all that much of the cash will go on payload tech rather than the ship itself, isn't chickenfeed.
Unfortunately the news comes too late for Roger Munk, who died in February: but one can assume that if he knew about the LEMV announcement he'd be very happy. ®
*It was actually quite common for the oldtime fully-buoyant 1930s ships to make use of dynamic lift at times, though the most successful operators - those of the German interwar zeppelins - cautioned against it as it rendered the ship liable to disaster if engine thrust was lost, and was also thought to overstress the ship.