Washington - Mar 28, 2003
The Space Race of the 1960s did not allow the time needed to develop reusable Space transportation systems. The requirement to beat the Russians led to the development of expendable capsules: the Mercury, Gemini, and Apollo spacecraft.
Reusable hardware in most applications offers cost savings over 'one use' expendable hardware. This of course is only true if the given hardware is planned on being used or operated many times. If it is not, then 'one time' or few use hardware is more cost-effective for a given application, as engineering and production costs are greater when designing for reusable systems.
Reusable First Stage (RFS) Defined As you probably know there are many different rocket designs being flown around the world. They are common to each other in that they all use multiple expendable rocket 'stages' in their designs. Since the 1960s and through today, every rocket has used expendable first stages. Once the stage has completed its job of accelerating the other stages and its payload to a specified height and speed, it is discarded where it breaks up and sinks to the bottom of an ocean. A combination of immature technology along with funding limitations has led to the delay in the introduction of more reliable and cost-effective reusable rocket designs.
The RFS acts like a traditional expendable first stage during its initial launch until separation occurs. After the RFS booster has depleted its fuel, it performs a jet-powered return to a runway. A rocket stage such as this that can be refurbished and reused again many times offers significant cost savings. In addition, a powered flyback stage offers inherent safety margins for the vehicle.
RFS and the Shuttle Following the Space Race, the country's focus fell back to the logical course of developing a reusable Space transportation system, the Space Shuttle we use today. For the lowest possible operating costs, a fully reusable vehicle was preferred. The original Space Shuttle design consisted of two reusable stages. A reusable flyback first stage and a second reusable stage composed of the orbital vehicle.
Budget cuts by the Nixon Administration nixed that promising design. After the Challenger disaster in 1986, the RFS gained more interest and supporters but was never able to receive the funding necessary to proceed. The Shuttle we use today utilizes what some people would call a reusable first stage system. The solid rocket boosters (SRBs) the Shuttle employs however are costly, dangerous, and have to be 'rebuilt' after each use. The ocean's salty waters causes corrosion to the boosters and the process of inspecting each booster after being pulled from the ocean and brought back to land for refueling is an arduous process.
The mid-to late 1990s saw NASA give Lockheed Martin and Boeing, the builders and operators of the Space Shuttle, small amounts of money to further design flyback boosters tailored for the Shuttle system as part of a possible upgrade program if it would be determined that the Shuttle would be flying for another twenty years. In this event, the reusable boosters would replace the Shuttle's current SRBs. The boosters would separate from the orbiter and external tank (ET) at around 31 miles (50 kilometers) and then land at a runway.
Originally the Space Shuttle system was to have a RFS and fly some 60 times a year. If we were to design and build an RFS today exclusively for the Space Shuttle, it would not be cost effective given today's Shuttle flight rates of 4 to 6 flights a year. Of course the uncertainty over how future operations of the Shuttle will proceed from here after the Columbia tragedy only adds to the unlikelihood of a Shuttle exclusive RFS ever being developed. NASA in the past five years estimated it would cost a minimum of $5 billion to bring 3 or 4 pairs of RFS boosters to operational status for the Shuttle, with the potential to save perhaps a few hundred million dollars per year in Shuttle launch costs given an average flight rate of at least 6 flights a year. This would mean it would take some 10 to 15 years of flying the Shuttle to just breakeven on the investment. Soon after the Shuttle would have to be retired anyways, leaving no new cost savings.
The cost analysis alone means the RFS has to be designed from the start to be universal, able to be applied to multiple vehicle concepts.
The Universal RFS Not only can a RFS replace the Shuttle's SRBs, but an appropriately designed 'universal' RFS will be able to launch a variety of different second-stage, or 'upper-stage' vehicles. The government-funded RFS will become the first stage for a host of launch vehicles and spacecraft. It will provide the first stage of a government-developed heavy lift launch vehicle (HLLV) for human missions to the Moon and Mars as well as other heavy payloads. This vehicle will likely incorporate many Shuttle elements such as the ET and perhaps the Shuttle's main engines, providing a low development/operating cost heavy lifter for government payloads. More importantly, the government-funded and developed RFS, too costly for commercial companies to develop on their own, will provide the 'boost' needed for the next generation of commercial Space 'shuttles' in the next decade.
This government investment enables the development of the next generation of specialized orbital spacecraft to be developed by small companies and entrepreneurs much more easily than would otherwise be possible as the companies would need to only develop their respective designs for the actual spacecraft, the orbital vehicle, rather than wasting time and money developing the expensive launch vehicle, or booster stage themselves. This will enable a large number of spacecraft designs and competitors in the human Space transport industry, and hence lower costs for everyone, as a variety of orbital 'spaceplanes' take to the skies.
The realization following the Columbia tragedy that the country needs more than a single means to transport humans to Space, allows this new opportunity to appropriately fund and build the RFS demonstrator to accommodate multiple vehicle designs by the end of the decade.
International Efforts American rocket scientists aren't the only ones that see a RFS as an appropriate evolutionary step in Space transportation. In particular, the European Space countries and Russia, have detailed designs for such a system for their respective launch vehicles.
Named the Baikal, the first stage of a new two-stage Russian rocket called Angara, the Russian flyback booster will rocket to about 38 miles (60 kilometers) before a second stage with payload separates for the final lift to orbit. After separation the main booster deploys a pair of wings and a jet engine fires up to return the flyback booster (s) to a runway landing.
In February of this year, Europe and Russia signed an agreement to expand their cooperation on developing new launch vehicle technologies. With Russian Soyuz launchers getting ready to be launched from the French Guiana launch complex, and the Baikal designed and ready to be developed pending funding, it appears that European Space Agency funding for a RFS booster for both Russian and European launch vehicles is in the making. In fact, the French Guiana launch complex may become the launch site for Russia's new generation of Angara launch vehicles.
The Entrepreneurs Reusable hardware for launch vehicles is such a logical next step that Space entrepreneurs have and continue to plan for such stages in their rocket designs. Beal Aerospace, a small rocket upstart from 1996-2000, intended on developing a RFS for its own line of rockets. More recently SpaceX, a launch company started by entrepreneur Elon Musk, aims to develop a two-stage launch vehicle consisting of a RFS. Starcraft Boosters Corporation has been advocating RFS boosters for the past few years. In 2002, the company received funding from the Air Force to proceed with the development of a small reusable technology demonstrator based on the company's designs.
RFS Today Studies have continued recently on RFS designs and systems under NASA's Space Launch Initiative program in the past two years. The Orbital Space Plane program, or 'mini-shuttle', which is now being accelerated, or at least fully funded following the loss of Columbia, is being designed to be able to be launched via a RFS.
Starcraft Booster's small development program was the start of the first real effort to develop a full scale RFS system, as actual hardware was built. Following this successful program a larger scaled size demonstrator will likely receive funding, building upon the experience gained from these early test flights.
At least an 80% scale test vehicle is required for this type of development program in order for the demonstrators test results to be 'traceable' in technology, operations, and subsystems to a full-scale operational vehicle. Such a demonstrator can be flying by the end of the decade.
Eventually as many as a dozen of these new boosters will make up a fleet of first-stage boosters for a variety of new commercially developed and operated orbital spacecraft that will follow the suborbital reusable launch vehicle market in the next decade.
The RFS for new Space transportation systems is the next 'stage' in Space transportation. After decades of studies, it looks as if its time has finally arrived!
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Rascal Program Selects Phase Two Contractor
Arlington - Mar 25, 2003
The Defense Advanced Research Projects Agency (DARPA) today selected Space Launch Corp., Irvine, Calif., to move into the 18-month second phase of the Responsive Access Small Cargo Affordable Launch (RASCAL) program.
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