WASHINGTON — Reduced demand for U.S. space launch services combined with surplus production capacity and reliance on foreign suppliers could have adverse long-term consequences for the nation’s propulsion industrial base and its ability to retain a qualified work force, according to a new report by the White House Office of Science and Technology Policy.

The congressionally mandated report, delivered to Capitol Hill Dec. 22, found that despite the importance of space to government and commercial activities, the U.S. launch industry has seen a decline in launch rates over the past decade. Meanwhile, propulsion companies report varying levels of capacity use, though industry-wide it appears to be roughly 50 percent or less than needed to meet demand.

The United States currently uses seven domestically built orbital and suborbital rockets to meet its unmanned space launch needs, with an additional two vehicles in development. Outside of NASA’s human spaceflight program and the Defense Department’s strategic missile efforts, demand for U.S. rocket propulsion systems comes primarily from three launch service providers: Denver-based United Launch Alliance, a joint venture of Boeing and Lockheed Martin; Dulles, Va.-based Orbital Sciences Corp.; and Hawthorne, Calif.-based Space Exploration Technologies (SpaceX).

Following a wave of consolidation over the last decade or so, U.S. propulsion production is concentrated among a handful of primary suppliers, including SpaceX, Minneapolis-based Alliant Techsystems (ATK), Pratt & Whitney Rocketdyne of Canoga Park, Calif., and Sacramento, Calif.-based Aerojet.

Since the late 1990s, U.S. space launch activity has flat-lined at relatively low levels, with the bulk of the demand coming from the U.S. government. In 1997, for example, there were 37 U.S. space launches, but since 2000 the rate has averaged only 19 per year. U.S. launch rates are expected to remain flat through at least the early half of the next decade, according to the report.

This contrasts sharply with forecasts of the 1990s, which envisioned burgeoning demand driven by an aggressive expansion of satellite-based Internet and telecommunications services. Those projections drove the U.S. Air Force to back development of two major new rocket families, the Atlas 5 and Delta 4, both of which now are being built and launched at lower-than-optimum rates, almost exclusively for government customers.

One of those vehicles, the Atlas 5, meanwhile, is powered by a Russian-built first-stage engine.

Because of the decision to use the RD-180 engine on the Atlas 5, “a substantial fraction of U.S. propulsion demand is now — and will continue to be for some time — filled by foreign suppliers,” the report states. “This dependence on foreign suppliers contributes to substantial overcapacity for U.S. space launch propulsion production, making it even more difficult for U.S. propulsion providers to sustain the industrial base in this area.”

At the same time, U.S. government agencies are limiting investments in space propulsion research and development, the report found.

In the global commercial launch market, meanwhile, U.S. manufacturers have been marginalized. From 2004 to 2008, U.S.-built rockets captured roughly 17 percent of the commercial market, compared with 42 percent for Russia, 21 percent for Europe and 18 percent for the multinational company Sea Launch, according to the report.

Commercial launch activity is expected to remain flat over the coming decade, meaning U.S. launch providers will not be able to count on growth in global market demand.

Already there has been substantial consolidation in the U.S. propulsion industry. Currently, Pratt & Whitney Rocketdyne is the sole supplier of high-thrust, high-performance liquid-fueled rocket engines, while ATK has cornered the market for solid-rocket motors. SpaceX builds lower-thrust hydrocarbon liquid-fueled engines for its own rockets, and Aerojet has significant capabilities in both liquid and solid motors, though the report notes Aerojet has less business than the other firms.

Despite this consolidation, industry-wide capacity utilization appears to be roughly 50 percent or less than needed to meet current demand, the report found. Given today’s demand projections, the U.S. launch services and propulsion industries will face significant challenges to sustaining these capabilities in the future.

As declining volume makes it harder for propulsion companies to hire new staff, and as uncertainty in the long-term job market makes the field less appealing to entry-level workers, industry also faces challenges in recruiting top talent, leaving companies dependent on an aging work force that will take its experience base with it upon retirement.

However, companies like SpaceX could buck the trend, the report found. A fledgling provider that in July successfully launched Malaysia’s RazakSAT Earth observation satellite atop its Falcon 1 rocket, SpaceX brings a new level of excitement and energy to the industry with the hope of new launch and associated propulsion systems at lower cost, leading to potential market growth.

“This allows them to attract a new cohort of entry-level scientists and engineers and provide hands-on experience with building and testing new engines and motors,” the report states, although it cautioned that such entrepreneurial space launch and propulsion capabilities are not yet fully proven. “Thus it is not yet clear what the full ramifications of these new launch services may be for the U.S. space launch propulsion sector.”