LOS ANGELES — An experimental robotic space plane developed for the Air Force is slated to launch today from Cape Canaveral, Fla., fueling an ongoing mystery about its hush-hush payload and overall mission.
Watching the pilotless spacecraft along with the Pentagon will also be wary Russian and Chinese military officials who have raised questions about U.S. intentions since the government launched its first version of the secret plane into orbit almost a year ago.
The X-37B Orbital Test Vehicle looks like a miniature version of the space shuttle. Because of its clandestine nature, some industry analysts have theorized it could be a precursor to an orbiting weapon, capable of dropping bombs or disabling foreign satellites as it circles the globe.
"It's a mystery, because the Air Force is being so closed-mouthed about the program," said Brian Weeden, a former Air Force officer and expert in space security. "It leads people to say, 'What exactly are they hiding?' "
Air Force officials have offered few details beyond saying the experimental space plane provides a way to test new technologies in outer space, such as satellite sensors and other components.
The first X-37B was launched from the Cape last April, and 224 days later it landed on its own — fully automated — on a 15,000-foot-long airstrip at Vandenberg Air Force Base, northwest of Santa Barbara, Calif. The plane being launched this week is also expected to land there late this year.
The space plane was built in tight secrecy by Boeing Co.' s Space and Intelligence Systems unit in Huntington Beach, Calif. Other components were kicked in from its satellite-making plant in El Segundo, near Los Angeles International Airport.
In recent weeks, the scheduled blast-off has drawn new attention. Lt. Gen. Oleg Ostapenko, commander of Russia's space forces, told state-run Novosti news agency that the military was following the development of the space plane. He said Russian scientists were developing similar technology.
Li Daguang, a professor at People's Liberation Army National Defense University in China, wrote an editorial that the technology "will soon have a revolutionary impact on space exploration." He went on to write that if the X-37B is used for military purposes, "it is capable of taking military actions against the enemy's satellite and space transportation devices."
Most U.S. military analysts are increasingly skeptical that the plane — in its current form — is a space bomber or satellite hunter.