The Air Force will launch their second X-37B space plane into earth orbit on Friday to begin a test flight which could last six months in space.
The nearly ten-foot high, twenty-nine foot long X-37B has a wing span of fifteen feet from tip to tip, and is designed to increase the military's knowledge of reentry style vehicles which can return experiments from space.
The first flight lifted-off last April 22 and flew what the Air Force deemed a successful flight of the unmanned craft. The only known issue was a tire which blew after landing upon runway 12 at Vandenberg, AFB in California.
Launch of the X-37B a top a United Launch Alliance Atlas 5-501 rocket is planned for March 4 at 3:39 p.m. EST, the opening of a two hour launch window, from complex 41 at Cape Canaveral Air Force Station.
This flight will mark the Atlas 5's twenty-fourth launch since it's first flight in 2002.
Several minutes into the launch, the Air Force will send the public into a news black out as this still top secret developmental Orbital Test Vehicle heads to orbit.
Several of this X-37B's flight details will go beyond the tests of the 224 day first X-37B flight last year. A payload or two will be flown on board the spacecraft.
The spacecraft will settle into an average orbit of about 350 statue miles.
ULA performed a fueled mock countdown of the Atlas 5 on February 4.
The Boeing Satellite Systems space plane uses bipropellant thrusters developed by American Pacific Corporation's In-Space Propulsion, and are used for vernier reaction control to achieve orbit; to change it's attitude while on orbit; and to leave orbit.
NASA begun the X-37 project in 1999, however the space agency handed it over to the Arlington, Virginia based DARPA (the Defense Advanced Research Projects Agency) five years later.
DARPA, originally formed in 1958 as the Advanced Research Projects Agency, is an office designed to prevent technological surprises against the United States, such as the Soviet Union's launch of Sputnik 1 in 1957.
The OTV project partnership between the military, DARPA and NASA was announced in October 2006.
The vehicle's return home is expected toward the end of this summer with an auto-landing at Vandenberg.