December 4, 2005 An American team has successfully demonstrated a radical new stratospheric airship, flying the aptly-named HiSentinel to an altitude of 74,000 feet. The development team of Aerostar International, the Air Force Research Laboratory (AFRL) and SwRI created the 146-foot-long airship which became only the second airship in history to achieve powered flight in the stratosphere. Designed for launch from remote sites, these airships will not require large hangars or special facilities. Unlike most stratospheric airship concepts, HiSentinel is launched flaccid with the hull only partially inflated with helium. As the airship rises, the helium expands until it completely inflates the hull to the rigid aerodynamic shape required for operation.