and multi engine designs than it is one of technological breakthroughs in thrust to weight ratios or other major performance factors. Looking ahead, it now appears that the inherent scalability of rocket vehicles combined with use of advanced technologies will support larger payloads in later generation vehicles. Even if the SSTO vehicles now being designed can be scaled up to heavy lift payloads in later generations this may or may not prove to be necessary. Instead it seem likely that standardized, reliable vehicles with twenty to fifty thousand pound lift capabilities should cause payload designers to adjust to their use rather than pay exorbitant additional costs for larger specialized loads. This is especially true when quick responses and rapid turnaround capabilities will make it easier to assemble structures in space. Making this Happen Theory as to what can now be done is fine but counting on it being done in order to plan projects that depend on it calls for some evidence that the reduced costs forecast will in fact be realized - and in what timeframe. Obviously this is what SPS designers are likely to be most interested in. It is now clear that first generation demonstration space transports able to provide cost effective transport at under $400 per pound, and possibly less, will fly before the turn of the century. This is based not on confidence in the paper proposals and theories of SSTO advocates but on the fact that, at long last, their initial development and demonstration is underway having been funded and contracted for by our Defense Department's SDI organization in early 1990. While there is still debate as to the specific characteristics and architecture of these specialized space transports, and what their initial payload capabilitieswill be, all those involved appear to be convinced there are no technological problems not readily resolvable. The SDI contractor programs are now approaching their Phase II task - that of designing a full, or possibly sub scale vehicle. In Phase II, which will start this summer assuming it is adequately funded, one or more orbital or sub orbital vehicleswill be built and tested. The key requirements these must meet are: (1) A medium payload to orbit of 15,000 to 20,000 lbs including crew members. (2) A turn around time of 7 days or less with surge capability and no more than 350 man days of support per flight. (3) High reliability: short flights with an engine out, all altitude abort and crew ejection. Ilie SSTO fleet is being designed to be both man and non man rated and flight certified from the onset just like commercial aircraft. We are looking for the option of deploying a fleet of these mini vans by the turn of the Century. The first fleet is being funded and developed by SDI in order to reduce deployment costs for Brilliant
RkJQdWJsaXNoZXIy MTU5NjU0Mg==