Abstract: A rocket engine has a combustion chamber and an expansion chamber interconnected by a nozzle. Both chambers and the nozzle are made of carbon fiber reinforced silicon carbide formed as a monolithic rocket engine body or formed in sections bonded to each other to also form such a monolithic rocket engine body. The rocket engine body is mounted in a support structure, preferably made of a metal. The rocket engine body sections are produced by mechanical machining of respective blanks made of C/SiC materials. Cooling channels and/or heat insulation structures are used for heat control. The insulation structures are preferably also made of C/SiC materials or of carbon fiber felts or of graphite film.

Abstract: An unfoldable and refoldable antenna reflector having support ribs which are linked to a support body, the support ribs being spaced from the latter approximately radially in the unfolded condition, for carrying a reflector screen or a reflector foil and which can be tilted up for refolding, folding elements being attached between adjacent support ribs which extend substantially transversely to the support ribs and are fastened at predeterminable spacings to the reflector screen or to the reflector foil, the spacings between the fastening points being shortened during refolding.

Abstract: An antenna reflector, for example for a satellite or spacecraft, has ribs urnalled to a central body by a first journal axis. Each rib has a radially inner section tiltable and lockable relative to the central body, and a radially outer section journalled to the inner rib section at a second journal axis for tilting and locking the outer rib section relative to the inner rib section. A motor driven cable drive and respective pulleys are so arranged that the inner rib sections are first partially unfolded before the outer rib sections begin to be unfolded. The outer rib sections then are moved faster than the inner rib sections so that both rib sections reach the fully unfolded state substantially simultaneously. The folding takes place in the reverse order, whereby the outer rib sections are folded first. The reflector netting is stretched out only after the ribs have been locked into the unfolded state.

Abstract: An umbrella type unfoldable antenna reflector net is supported by carrier bs extending radially from a carrier body and by auxiliary ribs extending between adjacent carrier ribs. Bracing wires are connected between the carrier ribs and the auxiliary ribs. The tension of the bracing wires, which in the unfolded state of the reflector net extend substantially in the direction of chords, is adjustable by respective adjustment members so that the bracing tension force has a force component which extends substantially perpendicularly to a plane defined by the unfolded reflector net. The adjustment members permit adjusting the reflector net into a parabolic shape.

Abstract: An unfoldable antenna netting reflector includes a plurality of stiff ribs to which the reflector net is secured. These stiff ribs are pivoted to a central holding member and extend radially outwardly when the reflector is unfolded to spread out the reflector netting. In order to assure a trouble-free unfolding of such a reflector at any time levers (8, 9) are provided between two ribs each (2, 4; 4, 6). Tensioning cables (14, 16) running over rollers (17, 19) are operatively connected to the buckling joints (8',9') of these levers for straightening out the levers. The ends of the levers are pivoted to the respective rib and the levers are capable of buckling in but one direction. When the levers assume the stretched out position, they snap into a locked condition. A plurality of ropes arranged for operating a plurality of levers may be operated in unison. The levers are secured to the ribs either at a spacing from the radially outer end of the ribs, or they may be secured to these radially outer rib ends.