The first public taste of rocket racing will take place Aug. 1 and Aug. 2 in Oshkosh, Wis., Whitelaw said, at the annual Experimental Aircraft Association air show. It will involve two of the sleek aircraft developed for the league. The racers will also perform at air shows in Nevada and New Mexico. (More information is available at rocketracingleague.com.)

Competition should begin in 2009, the founders said.

That is quite a bit later than the league planned. Rocket Racing was announced in 2005, and the company released animations showing what a race might look like, with plenty of swooping and blazing rockets. The founders said then that the first races would be held in 2006.

The league’s plans have faltered in the interim. A video game based on the races that the founders said would be produced has not emerged, and one of its original teams, Leading Edge Rocket Racing, dropped out last year, issuing a statement that suggested the league was in disarray.

“Some of the things took longer than we had anticipated,” Whitelaw said. He added, “We’re 15 months behind where I thought we would be, which is not too shabby.”

The league’s co-founder, Peter Diamandis, served as chairman of the X Prize Foundation, which awarded the $10 million Ansari X Prize in 2004 for the first privately financed human flight to space. Diamandis said in an e-mail interview that “most pioneers who enter this business are, typically, optimists, and tend to believe things can be accomplished faster than it really takes.”

The league, he said, fits into a broader goal of “making space a firsthand experience” for people, and driving down the cost of getting to space through commercial ventures.

Whitelaw stressed that the league was a business. It will patent technological innovations on its racers, like safety features, in hopes of making money off them should they make their way into general aviation, and it will try to build profits out of television and merchandising rights. The company will also sell conventional jet-engine versions of the Velocity racer, he said.