Abstract: An aerobrake for an orbital transfer vehicle that permits recovery of the vehicle for refurbishment and reuse after a payload has been deployed in a desired geo-synchronous earth orbit by slowing the vehicle for reentry of the vehicle to a low earth orbit for return to earth by a shuttle vehicle on the like for recovery and reuse. The aerobrake includes a flexible thermal blanket that is folded inwardly against the vehicle in a predetermined stored manner and which, after the payload is deployed, is driven to an extended position by power hinges that drive a plurality of supporting panel members that cooperate with drag links to provide a lightweight strong supporting structure for the thermal blanket.

Abstract: A heat exchange apparatus for transferring heat from a reactor gas coolant to a secondary fluid medium. The heat exchange apparatus comprises an elongated vertically extending hole in a concrete shield. Supported within the hole in spaced relation to the wall thereof is an elongated vertical extending tubular shroud which shroud has a gas entry at its lower end and a gas exit at its upper end. Means are provided for dividing the annular space between the shroud 16 and the wall of the hole into an upper and a lower region. Disposed in the shield is an inlet for reactor coolant which communicates with the lower region and is positioned vertically so as to be spaced above the gas entry to the shroud to thereby suppress natural convection during non-operating standby conditions of the apparatus. An outlet for reactor coolant, which is disposed in the shield, communicates with the upper region.