The single demonstrator used a retired Navy ZPG-2W blimp envelope and four Sikorsky H-34J helicopters. Navy contract for the Forest Service to demonstrate a heavy vertical airlifter for harvesting timber from inaccessible terrain. In forward flight, the ruddervators at the tail of the blimp also add their pitch and yaw control moments. Yaw moments are produced by the differential cyclic tilting of the rotors (i.e.
Propulsion and retardation are obtained from the cyclic tilt of the rotors, as for a normal helicopter. thrust) of the rotors gives powerful control forces. To maintain coincidence of the dynamic and static lifts (otherwise the envelope would pitch as helicopter power increased), it is impractical to use a single helicopter rotor, so multiple rotors are arranged around the center of buoyancy of the envelope.ĭifferential changes to the collective pitch (i.e.
#Cargolifter artist conception free
traveling to site without a payload) it would also free up the helicopters' rotor thrust for forward thrust, requiring less dynamic lift and lower fuel burn. This would give greater maximum lift capability for heavy-lift work. The Helistat concept was to augment the helicopters' dynamic lift with the static lift of an air buoyancy envelope. All the chords of the truss-arch are brace-connected to each other by diagonals (355 mm) and posts (273 mm), with the exception of the two bottom-chords these are connected by only straight members (355 mm) at 4.135 m, forming a Vierendeel-system.Artist's conception of the Heli-Stat in service The top chords (diameter 559 mm) are at 3.441 m centres and the bottom chords (559 mm) at 2.0 m centre. The arches of the cylindrical part have a structural height of 8 m and span over 225 m. The structure has been designed using steel grade S355.
In addition, this solution is suitable to avoid excessive wind turbulence. The shape of the building is oriented closely on the clearance diagram for two airships.
Both doors form a semi-circle in plan and a quarter-segment of a circle in elevation. The central part is of a cylindrical shape consisting of five steel arches at 35 m centres – each of the four bays being covered with a textile fabric – and at both ends of the building are the doors which consist of two fixed and six moving elements. The structural concept distinguishes two main parts of the building. Currently, the detailed design is taking place and most of the building structure should be ready in 1999. With a span of 210 m, a height of 107 m and a length of 363 m it will be the largest hall in Germany. The site is an airfield in Brand, about 50 km south of Berlin. In the middle of 1997 the CargoLifter AG commissioned the design for an airship hangar in Germany to house two new airships. This airship allows transporting a pay-load of 160t over a distance of up to 10’000 km with a speed of 80-120 km/h. Currently, a new generation of airships (helium filled, carbon fibre structure, length 260 m), the CargoLifter CL-160 is prepared. But the global market and ecological needs require the search for new forms of transportation. Six decades ago the golden age for the airships – succeeded by airplanes – seemed to have died forever.
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