U.S. Airforce's X-37B returns to Earth with a 'boom' and a new record for spaceflight – USA TODAY, USA Today

MELBOURNE, Fla. – Residents along the Space Coast may have heard a boom early Sunday asthe U.S. Air Force’s secretive, uncrewed X – (B spaceplane returned to Kennedy Space Center) after nearly two years in orbit.

The X – 37 B Orbital Test Vehicle completed its fifth mission, landing about 3: 51 am Sunday at KSC’s space shuttle landing facility for the second time. The 29 – foot Boeing spaceplane – about a quarter the length of a space shuttle – was greeted by workers in protective suits as it sat on the tarmac.

“The X – 37 B continues to demonstrate the importance of a reusable spaceplane, ”Air Force Secretary Barbara Barrett said in a statement. “Each successive mission advances our nation’s space capabilities.”

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The mini-shuttle was in orbit for 780 days for its latest mission, breaking its previous record of 717 days. The spaceplane – initially designed for an orbit duration of 270 days per mission – has spent 2, 865 days orbiting Earth. It is also considered the Air Force’s top premier reusable, unmanned spacecraft. Its mission experiments are typically kept top secret but have a focus on Air Force Research Laboratory experiments along with providing a lift into orbit for small satellites.

“The safe return of this spacecraft, after breaking its own endurance record, is the result of the innovative partnership between Government and Industry , ”Air Force Chief of Staff Gen. David L. Goldfein said in a release. “The sky is no longer the limit for the Air Force and, if Congress approves, the U.S. Space Force. ”

The shuttle’s latest mission launched Sept. 7, 2017, from Cape Canaveral Air Force Station on a Space X Falcon 9 booster. The next flight – its sixth – will launch from Cape Canaveral Air Force Station in 2020.

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