Inventors in America are claiming an altitude record for airships after a recent test flight in which an unmanned electrically-propelled helium dirigible successfully manoeuvred under power at 95,085 feet above the Black Rock Desert in Nevada. The "Tandem" craft is intended to demonstrate the first stage of radical plans which would see enormous, permanently inhabited "Dark Sky Stations" floating high in the atmosphere at the edge of space - to act as bases for radical hypersonic airships which would slowly fly themselves into orbit over a period of days using hybrid ion drive propulsion.
Somewhat more conventional extreme-high-altitude airships along the lines of the Tandem, flown above Nevada on October 22, would serve as shuttles carrying people and cargoes from the surface up to the colossal, mile-wide Dark Sky air/spaceports floating at 140,000 feet up.
The "Airship to Orbit" scheme comes to us from American DIY volunteer space collective JP Aerospace, founded by engineer John Powell, which has been developing high altitude balloons, rockets and combo rocket/balloon missions (aka rockoons, or in the parlance of our own Special Projects Bureau, ballockets) since 1979. JP Aerospace has now moved on beyond conventional rockoon flights to work on the use of small unmanned Dark Sky Stations as bases for vertical rocket launches starting from high up on the edge of space.
Both the Tandem and the prototype Dark Sky Station already flown use conventional helium balloons for lift, linked together by lightweight carbon-fibre trusses slung beneath. The Tandem features electrically driven propellors designed for the thin air found up at 100,000 feet and higher. One particularly neat trick is JP Aerospace's use of tied-down bags on the ground in which to inflate their balloons, meaning that there's no need to wait for windless conditions to make a launch.
Future manned ground-to-Dark-Sky ships and Dark Sky bases would use similar but more polished structures which would resemble huge cylinders of helium with lightweight keels running along them. Technically the ships would not be blimps – that's the term for airships without a rigid structure, which maintain their shape purely by internal pressure – but semi-rigids.
According to Powell, the two different types of ship and the intervening aerial base stations are vital as neither craft could survive the flight regime of the other. The vast, flimsy orbital vessels would be torn apart by the dense winds of the lower atmosphere, and the sturdier surface-launched jobs could never reach orbital velocity.