First rigid airship since the Hindenburg cleared for outdoor flight trials
Can brand new COSH tech finally revive the aerial leviathans of the 1930s?
COSH, lift and practical applications
Previous reports had suggested that COSH might need to work in conjunction with other plans such as taking off in a heavy condition, the use of suction landing gear to hold the ship down and perhaps supplementary water-recovery from exhausts to manage a truly major offload, but perhaps the technology has been improved.
COSH also offers the potential to eliminate another problem which contributed to the Walrus project's demise: the fact that a normal heavy-lift airship can't fly very high. If it does, its helium will expand to fill more space than there is inside the envelope and thus will be lost along with its lift as the precious gas bursts cells or escapes through automatic valves. Normally, the only way to get high is to take off with less gas, but that means less payload.
As a result, DARPA's Walrus was only expected to have a ceiling of 10,000 feet - in other words the huge, slow ship could have been hit by even shoulder-launched missiles from the ground all along its flight path. That, quite apart from the ballast issue, was probably a major reason for the project's demise.
But a COSH ship might do better, lifting off with a mostly full envelope and then stuffing the surplus expanding gas away into its internal pressure tanks as it climbed. The resulting loss of lift could be counterbalanced by dynamic lift generated by the ship's speed while it was in transit, perhaps letting it get survivably high up while cruising.
Descending to land, the COSH system would release the gas again to maintain a full envelope at low level and achieve neutral or close-to-neutral buoyancy for vertical landing, before cramming much of the helium away again during unloading. A COSH Walrus could thus be a lot more militarily practical than a non-COSH one.
Regardless of the details, if COSH works to any reasonable degree it is finally a new thing on the airship drawing boards after so many years and as such it could mean a genuine prospect of a return by the big rigids - enough to gladden any airship enthusiast's heart.
But the return will probably not be en masse, even if it comes. There are various possible military/security missions; there is the job of dropping exploratory drilling rigs or suchlike into remote locations. There aren't a whole lot of other likely applications for airships in today's world with its ships and planes, helicopters and roads and rails. It might be that the airship deserves to do some of the jobs that are done today by existing machinery, but not that many, and usually the margin isn't one that would let it break in against the established players. It'll probably be limited - if it comes at all - to jobs that nothing else can do, and there just aren't that many of those.
We're hoping we're wrong, here on the Reg airship desk, but we don't hold out much hope of a sky full of massive rigids any time soon. ®
*The last flight of the Graf Zeppelin II, sister ship to the Hindenburg. We do know about her, though she doesn't make nearly such a good headline.
We also know about the modern day NT Zeppelins and their rigid structures, but they are only semi-rigids: they need envelope inflation too.
No need to write in about those unless you really want to.