The Space Van is designed to carry 16 passengers -- plus a pilot, copilot and flight attendant -- to a 40-degree low Earth Orbit for $3,000,000 per flight in 1996 dollars. Figure 1 and the rendering above depict the passenger variant of the Space Van.
A highly similar cargo variant
is designed to carry 4200 kg. of cargo.
Space Tour is closely affiliated with Nevada corporations named Third Millennium® Aerospace, Inc., which will operate the Space Van and PanAero, Inc., which will design and build the vehicle -- if we are able to raise the funds required to bring the Space Van to operational status. Current plans are to start with the X Van, which we believe can be brought to operational status for perhaps 20 percent of the funding requried for the Space Van.
Pre-operational investment dominates the economics of a reusable launch vehicle. In fact, traffic levels must reach several hundred flights per year before recurring costs begin to become as important as recovery and return on initial investment. This is true, even though reduction of recurring costs is the driving force behind the development of reusable launch vehicles.
A relatively simple reusable booster that boosts the Space Van orbiter to about mach 3 at 30 km is the key to keeping the Space Van -- as well as the pre-operational investment -- relatively small. We call this type of booster an assist stage.
We define an assist stage as one that greatly reduces the size and cost of the expensive orbiter -- without greatly increasing the cost of complexity of the total system. A full-fledged reusable booster might stage at mach 6 and be far larger and more complex. Staging at mach 3 permits use of simple, pressure-fed rocket engines and virtually eliminates any need for thermal protection for the booster. Staging at high altitude also allows the orbiter wing and other aerodynamic surfaces to be designed by the sevenfold lighter reentry and landing weight.
Without staging, pre-operational investment might be ten or twenty times larger. Although payload might also be proportionately larger, this type of investment would be very hard to recover in a commercial business environment until the nature of the space transportation market has had a chance to change radically from what it is today. Ironically, a smaller vehicle like the Space Van can be the key to making a single-stage-to-orbit vehicle economically viable in the longer term. We recently gave a professional paper on this subject: AIAA-96-2773, The Economic and Technical Benefits of the Assist-Stage Concept for Space Launch (published by the American Institute of Aeronautics and Astronautics). A basically similar paper is published on this web site: The First RLV Should Be Small -- it's just good business. We have also co-authored a related article that appeared in the April 1997 issue of Aerospace America. Our later AIAA papers have emphasized and even smaller RLV, the X Van.
Thanks to the relief provided by the assist stage, the Space Van uses only existing engines and existing technology. This also reduces pre-operational investment. Our patented thermal protection system is an exception to current technology.
Although our main goal has been to minimize pre-operational investment, return on this minimized investment still accounts for about two-thirds of our proposed price per flight. Only about one-third of this proposed price is due to recurring costs.
The recent availability through Pratt & Whitney of the very rugged, high-performance, Russian-designed, kerosene/liquid oxygen RD-120 rocket engine -- when combined with a pair of the highly reliable Pratt & Whitney RL10A-4 liquid hydrogen/liquid oxygen rocket engines -- has resulted in a significantly improved orbiter for the Space Van. The gross mass of the improved orbiter is actually greater by 40 percent than our previous orbiter. However, engine costs are down by 50 percent. Moreover, the higher density kerosene results in a decrease, rather than an increase, in airframe costs. The new passenger variant has a gross mass of 86 metric tons and a reentry mass of about 12 tonnes. Overall length is 31.8 meters and span is 13.5 m.
Cargo Variant: The cargo variant of the orbiter of the Space Van is unmanned and features a container section that is removable prior to reentry -- with the nose reattaching to the front end of the liquid oxygen tank. This allows the relatively small orbiter to carry more sizable cargo loads than would otherwise be possible for this size vehicle. Instead of the removable containers, the cargo variant of the Space Van can carry prefabricated habitat, tankage or other modules that are 4 meters long and 3.2 meters in diameter. We plan to use various types of these modules for our planned space tourist facility. After separation of the payload, the center of gravity of the cargo variant is significantly further aft than for the passenger variant; this results in a delta wing for the cargo variant. However, tankage, fuselage, engines, tail and other components should be nearly identical to those for the passenger variant.
Both the passenger and cargo variants of the orbiter feature novel movable stabilizers that provide longitudinal and directional stability at hypersonic speeds. The fixed dorsal (topside) fin is effective subsonically and at low angle of attacks supersonically. However, neither the fixed dorsal fin on the Space Shuttle nor on the Space Van is effective at high angles of attack during reentry. For this purpose, the movable stabilizers are moved aft and rotated down to within 45 degrees of the vertical to provide both directional and longitudinal stability at high angles of attack and at hypersonic speeds. Ventral (underside) fins can be very effective for this purpose; however, ventral fins can also cause severe heating problems. We avoid heating problems by moving the stabilizers aft of the body for reentry. The movable stabilizers are in the forward position shown above for the passenger variant at all times other than during reentry at hypersonic and supersonic speeds.
Assist Stage: The unmanned assist stage is the key to making the Space Van such a promising concept. We believe that an assist stage can be generally much less complex and costly than what most people would have in mind when they think of a booster for a full-fledged, two-stage system. We believe that pressure-fed engines can permit staging at supersonic speeds with a relatively simple, low-cost, reusable booster.
The new orbiter enabled by the RD-120 rocket engine is a recent development. Accordingly, we do not yet have presentation-quality drawings of the total system and the assist stage. However, the basic concept remains similar -- although system gross mass has increased from 250 tonnes to 350 tonnes, and orbiter gross mass has increased from 61 tonnes to 86 tonnes. The earlier system is depicted in figure 2. The earlier assist stage is depicted in figure 3.
Bringing the Space Van to operational status is a funding problem -- not a technical problem. The Space Van can be operational four years after the start of serious funding. We may want to build and to operate the X Van first, in order to raise adequate funds for the Space Van or an even larger SSTO.
We don't want to mislead you. So we'll tell you up front: Third Millennium Aerospace, Inc., Space Tour, and PanAero, Inc. have no paid employees at this time. However, we have had a lot of help and encouragement from a lot of people on an unpaid basis because these people believe in our project. Moreover, we have a network of very talented individuals and companies that we can activate with proper funding. The history of the aerospace industry shows that the best projects have been run by very small project groups. There is no reason why a small company --or even a virtual company -- cannot host a small project group. We've done a lot without funding. Just think what we can do with your help!
Third Millennium and Len Cormier, president of Third Millennium, have sustained themselves for three decades through a wide variety of aerospace consulting and engineering contracts.
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