Nearly two years after it launched, the US Air Force’s reusable, unmanned X-37B Orbital Test Vehicle ended its classified mission on Sunday, becoming the first spacecraft in nearly six years to touch down at the Kennedy Space Center’s Shuttle Landing Facility in Florida.
It was the fourth mission for the USAF’s X-37B program, and according to Space.com it was by far the longest lasting, as the robotic plane circled the Earth for 718 days – 44 days more than the previous X-37 flight, which remained in orbit for a period of 674 days, the website noted.
The recently-concluded mission was the fourth for the X-37B program, which is operated by the USAF’s 45th Space Wing at Patrick Air Force Base in Florida, but the first to land in Florida, as previously the space planes landed at Vandenberg Air Force Base in California upon their return. The change is part of the Air Force’s attempt to consolidate the program’s operations.
In a statement, 45th Space Wing commander Brig. Gen. Wayne Monteith called it “an incredibly exciting day” for the division. “Our team has been preparing for this event for several years,” he continued, “and I am extremely proud to see our hard work and dedication culminate in today’s safe and successful landing of the X-37B.”
“The landing of OTV-4 marks another success for the X-37B program and the nation,” X-37B program manager Lt. Col. Ron Fehlen added. “This mission once again set an on-orbit endurance record and marks the vehicle’s first landing in the state of Florida. We are incredibly pleased with the performance of the space vehicle and are excited about the data gathered to support the scientific and space communities.”
Top-secret program being used to evaluate spaceflight technology
While the exact nature of the X-37B’s mission remains classified, Air Force officials explained that the goal of the program is to perform risk reduction experiments and to test out concepts of various technologies for use in the development of future multi-use space travel vehicles.
“The hard work of the X-37B OTV team and the 45th Space Wing successfully demonstrated the flexibility and resolve necessary to continue the nation’s advancement in space,” Randy Walden, director of the Air Force Rapid Capabilities Office, explained. “The ability to land, refurbish, and launch from the same location further enhances the OTV’s ability to rapidly integrate and qualify new space technologies.”
The space plane that landed at the Kennedy Space Center on Sunday is one of two that the USAF is known to possess, according to Space.com. The vehicles are similar in appearance to the space shuttles formerly used by NASA, but at just 29-feet in length, are much smaller than those iconic (now retired) vehicles, the website explained. Like the space shuttle, the X-37B lifts off from the vertical position but lands horizontally upon its return to Earth.
Each of the Orbital Test Vehicle (OTV) missions has lasted longer than its predecessors. The first X-37B launch, OTV-1, lifted off in April 2010 and remained in space for just 224 days. Its successor, OTV-2, launched the following March and remained in orbit for 468 days. The OTV program has spent a combined 2,085 days orbiting the Earth, according to the Air Force.
Image credit: Secretary of the Air Force Public Affairs