Search Results

The Near Infrared Camera and Multi Object Spectrometer (NICMOS) was installed in the Hubble Space Telescope in February 1997. Shortly thereafter, the instrument experienced a thermal short in its solid nitrogen dewar system which will shorten its useful life significantly. A reverse Brayton cycle mechanical refrigerator will be installed during the third servicing mission (SM3) to provide cooling for the instrument, and thereby extend its life. A Capillary Pump Loop (CPL) and radiator system has been designed, built and tested to remove up to 500 watts of heat from the mechanical cooler and its electronics. This paper will describe the CPL system in detail and present the results of the extensive testing and qualification program.

This paper presents the results of a design study of a low cost Jet Fuel Starter (JFS). The JFS is a small free turbine turboshaft engine with a peak output of 150 horsepower. The design concentrates on high output per unit volume and weight, and on low cost. A low speed, four stage axial compressor design results in a compact, lightweight starter. Die castings and a radial pin construction for both the static structure and the compressor rotor provide the most significant cost savings over conventional gas turbine fabrication methods. The low speed concentric shaft design (approximately 70 percent of usual design practice) permits a simple two bearing shaft suspension for both rotors. The resulting close coupling of the turbines reduces the number of expensive hot end components to only five parts.