USA-277, also referred to as Orbital Test Vehicle 5 (OTV-5), is the third flight of the second

Boeing The Boeing Company () is an American multinational corporation that designs, manufactures, and sells airplanes, rotorcraft, rockets, satellites, telecommunications equipment, and missiles worldwide. The company also provides leasing and product ...

X-37B The Boeing X-37, also known as the Orbital Test Vehicle (OTV), is a reusable robotic spacecraft. It is boosted into space by a launch vehicle, then re-enters Earth's atmosphere and lands as a spaceplane. The X-37 is operated by the United State ...

, an American unmanned vertical-takeoff, horizontal-landing

spaceplane A spaceplane is a vehicle that can fly and glide like an aircraft in Earth's atmosphere and maneuver like a spacecraft in outer space. To do so, spaceplanes must incorporate features of both aircraft and spacecraft. Orbital spaceplanes ten ...

. It was launched to

low Earth orbit A low Earth orbit (LEO) is an orbit around Earth with a period of 128 minutes or less (making at least 11.25 orbits per day) and an eccentricity less than 0.25. Most of the artificial objects in outer space are in LEO, with an altitude never mor ...

aboard a Falcon 9 rocket from LC-39A on September 7, 2017. Its mission designation is part of the USA series. The spaceplane was operated by Air Force Space Command, which considers the mission classified and as such has not revealed the objectives. However, the Air Force did reveal that among the onboard payloads was an experimental oscillating heat pipe. Additionally, it was revealed after OTV-5 landed that it had deployed three

cubesats A CubeSat is a class of miniaturized satellite based around a form factor consisting of cubes. CubeSats have a mass of no more than per unit, and often use commercial off-the-shelf (COTS) components for their electronics and structure. CubeSats ...

in orbit.

Mission

OTV-5 is the third mission for the second X-37B, and the fifth X-37B mission overall. It flew on Falcon 9 booster B1040 from Kennedy Space Center Launch Complex 39A, which touched down at Landing Zone 1 following launch. It was fastest turnaround of a X-37B at 123 days. OTV-5 was deployed into an

orbital inclination Orbital inclination measures the tilt of an object's orbit around a celestial body. It is expressed as the angle between a reference plane and the orbital plane or axis of direction of the orbiting object. For a satellite orbiting the Earth ...

of 54.5°, higher than previous X-37B missions. The Air Force has not disclosed the reason for this. After a record-setting 780 days in orbit, OTV-5 returned to land at the Shuttle Landing Facility on October 27, 2019.

Satellite Deployments

Sometime during its orbital mission, OTV-5 deployed three

, given the designations USA 295, 296 and 297. The deployment was not announced until after OTV-5 had landed, which led to many accusing the US of breaking the Registration Convention. The convention, which the US has ratified, requires newly deployed satellites to be promptly registered with the United Nations Office for Outer Space Affairs.

References

{{Orbital launches in 2017 Spacecraft launched in 2017 Satellites of the United States Air Force Spacecraft which reentered in 2019 USA satellites Boeing X-37

Mission

Satellite Deployments

See also

References