NASA has offered old programs for sale to the commercial market. Sierra Nevada purchased the rights to the Dream Chaser as a retired NASA project that was following a Russian program. So we DO have a space junk yard. NASA has been directed to salvage parts of the Shuttle for the Space Launch System. Technology from the Shuttle is living on in the X-37 Air Force space plane. If the pattern goes on, the Space Launch System will generate parts that may never fly. Even if SLS does fly, it is an expendable booster and will be a target for budget cuts. Perhaps we can plan on salvaging this and making a reusable system. So my monster plane idea may have a future with discount salvage yard parts. So I don’t feel bad about looking at my ideal solutions here. For the commercial market this could be bargain day.
I did a horizontal launch design exercise with the SLS tanks and engines. Instead of single fuel and oxidizer tanks, I split the two tanks into four. With four tanks side by side all the fuel line manifolds are at the rear near the engines. This adds a manifold, but eliminates the long fuel line from the front tank. It also packages the tanks as tapered to fit in the airfoil shape.
In place of the giant solid boosters, we may expect to use smaller solids on the booster, and hybrid rockets on the second stage. This is essentially a third stage, but eliminates recovering boosters from salt water and reentry heat damage. The empty solids can be returned with the boosters. These may be small enough to avoid the vulnerable segments of the shuttle boosters. Aerojet makes solids for the Atlas 5 which may be suitable.
Horizontal launch doesn’t need the massive thrust of vertical launch. We hope to sustain the gradual acceleration with air-breathing turbines to eliminate part of the oxidizer payload. The initial proposal offers 16 Pratt Whitney F-100 turbine engines for a total sustainable thrust of 464,000 lbs on afterburners. But our focus is not propulsion innovation for this study. We look to position an efficient reusable airframe for the best available propulsion. This should be flexible enough to welcome and facilitate new propulsion developments. The potential is ready for Scramjets or Reaction Engines Sabre concept. Their unmanned vehicle targets single stage to orbit, but the propulsion may be applicable to even heavier manned vehicles in staged operations. For any staged operations lining the stages up will reduce frontal area and total vehicle size and mass. We hope to offer the best possible airframe for any propulsion combination.
Now we have two stages, but still want a safety factor. The TAAS company has patented an aircraft escape cabin which offers more than mere survival. http://www.taascompany.com/services We are looking at a reentry vehicle scaled up from the X-37 space plane. This is the world’s only operational space plane since the shuttle was retired. A working design is the best role model for reentry, so we applied it here.
X-37 PASSENGER VERSION?
OUR RESCUE VEHICLE FOR 2 MAN CREW AND 18 PASSENGERS!
Safety is a key issue on this vehicle because it lends itself better to manned operations. Reusability demands expensive development and reliability testing. This is also desirable for manned operations. It may be hard to compete with vertical launch in heavy lift flights, but human operations, especially civilian, will require this effort. Mass fraction favors vertical launch, but reusability and safety help to justify the loss. Here is a first peek at a possible solution.
COMPARISON OF SLS AND HORIZONTAL LAUNCH SYSTEM WITH COMPARABLE PROPELLANT VOLUMES
After investors the next important booster may not be the first stage of the flight vehicle. It may be time to consider rail launch again for several reasons. For horizontal launch a massive space tanker is a challenge to rubber tires. Tire failure doomed the Concorde liner. Landing gear for takeoff must be massive and are only dead weight in flight. If we rail launch the landing gear can be much lighter for empty landings. An early launch abort with full tanks would force a booster landing in water, with the upper stage making a runway landing with passengers. Booster loss would be the sacrifice risk for a rail launch, but not crew safety.
Rail launch systems may not need to use mag-lev. Rockets generate gas which could be blown over rail shoes like an air hockey table. There could be a mini-ground effect air cushion on the rail pads. Initial acceleration can be aided by turbine or rockets with retro rockets for launch abort. A long rail would leave a lot of time for abort decisions and a safe stop. The upper stage vehicle may be able to eject during this phase as well. With a rail launch the pilot is relieved of cross wind issues and other flight challenges. For an aircraft of this size and explosive potential this will be a great relief. Safety is a primary advantage of controlled initial launch guidance. Some fuel will be conserved as well.
A CRUDE BOX ON RAIL AIR CUSHION CONCEPT…AIR HOCKEY!
Hydraulics could raise the delta wing aircraft for takeoff rotation. The Concorde was designed to create a vortex that increased lift in high angle of attack flight. This eliminates the mechanical flaps we often see in commercial aircraft. Every little advantage helps to move the difficult design closer to being an operational system.
Now you have seen the introduction to an investigation. I don’t have all the answers, but I might have some of the questions. Are there more combinations of good ideas and systems to be considered for space launch? Our new space industry is building on this hope.