Reducing the high costs of placing a satellite into orbit has been a major goal for the aerospace industry for years. The current cost of sending up a satellite starts at a couple thousand dollars per kilogram on unmanned, expendable boosters like the Atlas and Delta. Reusable launch vehicles (RLVs), however, could put satellites in orbit for significantly less.

At least one of these promising new rockets is preparing to fly. Roton, which is being built by Redwood City, Calif.-based Rotary Rocket Co., is ready to begin atmospheric test flights. If all goes according to plan, the cone-shaped Roton will take off like an ordinary, single-stage rocket. After delivering its satellite payload in orbit, the vehicle will re-enter the atmosphere, sprouting a set of rotor blades that allow it to land like a helicopter.

The Roton is one of several RLVs that could be in service within two to three years-if companies can raise the money needed to build the vehicles. Indeed, for RLV hopefuls the hardest part may not be developing the technology but obtaining the money needed for construction. Rotary has been one of the more successful companies, but while it has raised $30 million-enough for a full-scale prototype-it will take another $120 million to build the first commercial Roton. Rival Kistler Aerospace has raised more than $400 million for its two-stage RLV, but still needs several hundred million more. Others have generated only a tiny fraction of their needed funding.

If RLVs show such promise, why aren’t investors more interested? A major concern is the uncertain size of the market. Most proposed RLVs are best suited for launching small satellites into low orbits (typically less than 1,500 kilometers). Hundreds of these satellites will form the infrastructure of the global telecom systems for companies like Iridium, Globalstar and Teledesic. But with Iridium facing financial problems and with Teledesic’s design in flux, demand for RLVs is uncertain. The proposed RLVs are not powerful enough to lift heavy communications satellites 36,000 kilometers up into geosynchronous orbit for broadcasting television and other signals-the faster-growing segment of the business.

Still, developers of RLVs are not daunted. Gary Hudson, CEO of Rotary, notes that RLVs like Roton would be capable of servicing satellites already in orbit and delivering crews to the International Space Station, not just launching satellites.

If RLVs can deliver on their promise of low-cost space access, they may open up markets such as rapid cargo delivery or space tourism. Attempting to predict such a future, says RLV advocate Max Hunter, would be like “explaining Hollywood to Queen Isabella.”