MIRACULOUS new AIRSHIP set to fly by 2013
Helium buoyancy issue solved at last?
Some problems can only be solved with a COSH
Enter Pasternak with his COSH equipment, which compresses helium into tanks, so removing lift and adding weight. These tanks, judging by Aeros photos of test blimps, are large low-pressure affairs perhaps made of fabric or other lightweight stuff rather than conventional metal high-pressure jobs. The helium is compressed only enough that it becomes heavier than air rather than lighter – say to pressures of just a few atmospheres, no more than that inside some modern bicycle tyres. (The toroidal tanks used on previous Aeros test blimps somewhat resembled large bike tyres, in fact: a doughnut shape is particularly efficient at containing pressure.)
Aeros blimp without COSH.
Pasternak contends that COSH would allow an airship to unload cargo or passengers without taking on ballast or venting gas: instead, enough helium would be rammed into the pressurised cells to compensate for the lost weight of payload. Apparently this can be done in a practical amount of time using condenser/compressor machinery of reasonable size, weight and power requirements.
Originally, Pasternak and Aeros intended to use COSH to build a mighty "Walrus" ship for the famous military crazytech agency DARPA. The Walrus was meant to lift an entire US ground-combat battalion and all its vehicles and equipment in a single load, and drop them off more or less anywhere – ie, do so without taking on ballast.
Same blimp, with COSH. Note the doughnut tanks.
Sadly, Walrus was cancelled by Congress in 2006: perhaps reasonably enough. In order to lift its enormous load the Walrus needed to fill a large fraction of its vast hull with lifting helium, meaning that it would reach pressure height at a fairly low altitude of just 10,000 feet – putting the huge, slow titan within the reach even of basic man-portable antiaircraft missiles all along its line of flight.
Other major airship projects remain – the US Army's LEMV, for instance, and DARPA's ISIS – but these are intended to operate at higher altitudes on surveillance missions and so would not offer massive payloads (though the LEMV could perhaps serve in a cargo role if desired). Since Walrus' cancellation, however, Aeros has been left out in the cold – though DARPA has nonetheless funded a small-scale COSH demo and some work on the innovative rigid shell required for a full-fledged "Aeroscraft".
Now, however, Aviation Week reports that Aeros has new funds from the Pentagon's Rapid Reaction Technology Office. The company now expects to fly a demonstrator dubbed "Pelican" either next year or in 2013. The 230-foot Pelican will not carry any payload, but will prove the rigid aeroshell, the COSH technology and the integrated flight-control system that will use the COSH system in conjunction with vectored thrust from the propulsion (and dynamic lift in forward flight) to handle the craft and achieve full vertical-takeoff-and-landing (VTOL) performance. This last is important as many of the newer "hybrid" airship designs are not true lighter-than-air vessels: they are intended to operate in a heavy condition, in large part to deal with the issues of fuel burn and/or unloading. This means that they are likely to need to take off and/or land running, like an aeroplane: it also means that they cannot remain airborne in the event of engine failure, nor unload or load in the hover like a helicopter.