An Air Force X-37B space plane is continuing to set a new record for spaceflight-duration, at over 719 days of orbital spaceflight during its mystery mission that no one knows about.
The Air Force’s Orbital Test Vehicle 5 (OTV-5) mission passed the record for spaceflight time of 717 days, 20 hours and 42 minutes previously held by the previous Orbital Test Vehicle 4 (OTV-4) mission on Monday, and surpassed 719 days according to reporting from Space.com
The X-37B space plane, a pilotless drone, was initially launched with the assistance of a SpaceX Falcon 9 rocket.
“The primary objectives of the X-37B are twofold; reusable spacecraft technologies for America’s future in space and operating experiments which can be returned to, and examined, on Earth,” an Air Force press release said last year.
The press release further stated the X-37B is the Air Force’s first vehicle since NASA’s shuttle orbiter that can return test equipment to Earth for closer inspection.
Particularly, the X-37B has tested equipment including advanced guidance, navigation and control systems, thermal protection systems, avionics, high-temperature structures and seals, lightweight electromechanical flight systems, and advanced propulsion systems.
The X-37B was developed primarily by Boeing and the concept for the program originated with NASA in 1999 as the X-37 program before it was transferred to the Defense Advanced Research Projects Agency, DARPA, in 2004.
The X-37B is powered with Gallium Arsenide Solar Cells with lithium-Ion batteries. The Air Force space plane is 29 feet, 3 inches (8.9 meters) in length, 9 feet, 6 inches (2.9 meters) in height and has a wingspan of 14 feet, 11 inches (4.5 meters).
The space plane has an 11,000 pound launch weight which can be carried and launched by either the Space X Falcon 9 rocket or a United Launch Alliance Atlas V rocket. It is designed for take-off aboard a rocket, and horizontal landing on an airplane runway.
Each of the OTV missions starting with OTV-1’s launch on April 22, 2010 has taken off from Cape Canaveral Air Force Station in Florida. The first three OTV missions landed at Vandenburg, Air Force Bace in California and the fourth mission landed at the Kennedy Space Center in Florida.
The first four Orbital Test Vehicle missions clocked a total of 2,085 days of orbit, facilitating the testing of space planes reusable flight features, re-entry and landing technologies and other experiments intended to the national space community. The current OTV-5 mission began on September 7, 2018.
The Orbital Test Vehicle 5 mission is still at only a fraction of overall spaceflight duration records. Communications satellites typically remain in orbit for around five years. The NASA Voyager probes have been in flight for over four decades now.