Ground based and airborne infrared astronomy is limited by atmosphere and telescope heat. These systems require a cold helium cooling of the instruments with a dewar for cryogen storage. Given the limited lift capability of a scientific balloon, the dewar mass is of critical importance. For structural, low mass flight applications, carbon fiber is a clear winner. GTL has developed BHL™, a micro-crack free, re-usable carbon fiber material for use in cryogenic vessels. GTL’s BHL is well suited for the application of the liquid helium dewar, with low mass, low thermal mass, and low thermal conductivity as carbon fiber is an excellent insulator at < 20K, far better than glass-fiber or epoxy itself.
The proposed effort is directly relevant to NASA future mission planning. This is an enabling technology for a new generation of balloon-borne cryogenic observatories. Large (3 meter) cooled telescopes at balloon altitudes would have up to 100,000 times faster mapping speed than the current state of the art (SOFIA's ambient temperature telescope at 39,000 feet).
The BHL technology applied to dewar systems offers significant improvements over current state-of-the-art dewars. BHL will provide for reduced boil-off, reduced cost, and easier transport of the dewars. BHL dewars could be applied to a large number of NASA systems. Anywhere cryogenic fluid is stored could potentially be replaced with these low mass, high efficiency composite dewars. NASA space systems, lunar and Mars landers, lunar and Mars habitats, as well as long term storage could benefit greatly from low mass BHL dewars and/or cryotanks.
For the same reasons that these composite dewars would be so beneficial to NASA, they would also be beneficial to the DoD. These low mass dewars could enable aircraft to run off of other fuels, such as liquid natural gas and liquid hydrogen. In the private sector BHL cryogenic dewars could be implemented in hospitals, research corporations, and cold gas/welding suppliers.