Aeronautics and astronautics – Spacecraft – Spacecraft formation – orbit – or interplanetary path
Reexamination Certificate
2001-02-23
2002-03-26
Barefoot, Galen L. (Department: 3644)
Aeronautics and astronautics
Spacecraft
Spacecraft formation, orbit, or interplanetary path
C244S164000, C244S172200, C244S002000
Reexamination Certificate
active
06360994
ABSTRACT:
FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT
None
FIELD OF THE INVENTION
The present invention pertains generally to space launch vehicles. More particularly, the present invention pertains to a configurable space launch system of space launch vehicles. The present invention is particularly, but not exclusively, useful for providing assembly of components of a space launch vehicle selected to accomplish a specific mission or task at the lowest possible cost.
BACKGROUND OF THE INVENTION
Manned and unmanned spacecraft have ventured far beyond Earth and its sensible atmosphere. Space exploration activity has collected valuable data about human and other biological, physiological and psychological reactions to the space environment. Other space exploration activities have greatly expanded our knowledge of Earth, its moon, the solar system and the universe.
Parallel with space exploration activity, substantial use of Earth orbits for military and commercial applications have developed. Presently, the majority of space launches are for military and commercial purposes. Examples include communications satellites, weather satellites, Earth observation satellites, and navigation satellites.
The feasibility and capability to launch spacecraft into Earth orbit, and beyond, clearly has been demonstrated. The size of a space launch vehicle is primarily a function of the payload mass, the apogee of the operational orbit, the perigee of the operational orbit, the inclination of the operational orbit, and the technology applied in the launch vehicle design. The cost of a space launch typically is tens to hundreds of million dollars. Reducing costs, therefore, associated with multiple and frequent space launches is a primary goal of space activity.
Reusability of space launch system components is a logical and presently favored path to lowering the costs associated with a space launch. The U.S. National Aeronautics and Space Administration Space Shuttle is a partially reusable system. The solid rocket booster units associated with the Space Shuttle are recoverable; after a parachute landing of a booster unit in the ocean, parts of a booster may be recycled. The orbiter unit associated with the Space Shuttle has thermal protection, an aerodynamic shape adequate for providing lift in a variety of situations, aerodynamic control surfaces, the capability of entering Earth orbit and returning to Earth's surface for horizontal landing on a runway, and therefore is recoverable intact for later launches. The orbiter unit was the first operational “spaceplane.” The third system component of the Space Shuttle is a single external tank, which is expended after each launch. The basic design of the Space Shuttle was done in the 1970's.
At least one principal disadvantage of the manned Space Shuttle is the relatively high cost per flight, which, in fact, is higher than contemporary unmanned expendable launch vehicles of the Atlas, Delta, Ariane and Proton families. Therefore, what has been sought in the industry, but not achieved, is a new configuration with a cost-per-flight lower than contemporary expendable launch vehicles.
Considerable study, analysis and preliminary design activity has focused on a fully reusable single spaceplane. Unfortunately such an approach, while theoretically possible, has been found to be impractical in terms of technological risk. A relatively small increase in the dry weight of the single spaceplace results in an unacceptably large increase in the gross lift-off weight of the vehicle. Further, projected development costs are quite high. Another approach involves two fully reusable spaceplanes of different sizes, one spaceplane being a large reusable booster, and a smaller reusable spaceplane attached to the first in parallel. This approach reduces some of the technological risk associated with a fully reusable single spaceplane, but because two separate reusable spaceplanes must be developed, development costs appear prohibitive.
Over the past decade, numerous alternative efforts have examined various vehicle configurations for lowering the cost-per-flight. The typical result is a concept that requires considerable expense to develop, acquire and operate, that can be applied only to relatively low mass payloads, or both. Therefore, there is a continuing need in the industry for a new, useful and improved space launch system of vehicles that is capable of providing the lowest cost-per-launch possible for a broad spectrum of space launch missions.
The principal components of cost-per-flight are launch site operations, launch range operations, propellant, expendable hardware, turn-around costs for reusable hardware and financial return. At least one way to assess required financial return per flight is the technique of Internal Rate of Return. For example, the development and initial fleet purchase cannot exceed $1.5B if (a) the development period is four years, (b) the operations period is six years, (c) the launch rate is 25 per year, (d) the required Internal Rate of Return is 30%, and (e) the cost per flight is to be fifty percent of contemporary expendable vehicles. That, in turn, emphasizes the need for relatively low development investment and relatively low investment in the initial fleet of reusable hardware.
The present invention responds to the significant challenges in lowering the cost-per-flight of space launchings.
SUMMARY OF THE INVENTION
Although there are many challenges associated with low cost-per-flight space launches, the goal remains achievable. It would be desirable, and of considerable advantage, to provide a space launch system of vehicles that have the lowest cost-per-flight for a broad spectrum of space launch missions. To meet the need for low cost-per-flight, such a system of vehicles should have substantial commonality of components and technology. Each system family member, therefore, would have strong configuration similarities to all other family members. Throughout the decision process of selecting appropriate components for such a space launch system, the investment cost for system development and for initial fleet purchase of reusable components, if any, would be included in predicting cost-per-flight. Applying this overarching rationale, the lowest cost-per-flight is achieved by the present invention, a configurable space launch system.
Briefly, a configurable space launch system, according to the present invention, is a family of distinct vehicle configurations, wherein each configuration includes one or more system-common reusable spaceplanes and a plurality of detachably mounted liquid propellant tanks that are external to the one or more spaceplanes. In extending beyond the existing art, (a) each vehicle configuration excludes ascent propellant tanks permanently installed inside, or integrated into, a reusable spaceplane, and (b) each vehicle configuration is operated in flight such that the number of in-flight staging points, where essentially empty external tanks and/or reusable spaceplanes no longer needed for acceleration thrusting are detached from the vehicle, is greater than the number of reusable spaceplanes in the configuration. The system-common reusable spaceplane has a payload bay dimensioned for the largest projected payload, incorporates one or more main rocket engines, and is capable of entering the Earth's atmosphere for landing. Different vehicle configurations within the space launch system of vehicles will involve variations in the combination of number of spaceplanes; the number, size, and location of external tanks; and the number of in-flight staging points. The resulting space launch system is configurable because a vehicle configuration may be tailored for specific missions at optimal low cost-per-flight.
As used in this document, a “space launch vehicle” travels from the surface of the Earth to Earth orbit and is comprised of one or more common spaceplanes and multiple external tanks.
A “spaceplane” is a component of the space launch vehicle, and is, at least, fully reusable by returning from orbi
Geyer David W.
Hart Don A.
Barefoot Galen L.
Don A. Hart & Associates, Inc.
Law Offices of Ray R. Regan
LandOfFree
Configurable space launch system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Configurable space launch system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Configurable space launch system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2827823