USA-277
USA-277, also referred to as Orbital Test Vehicle 5 (OTV-5), is the third flight of the second Boeing X-37B, an American unmanned vertical-takeoff, horizontal-landing spaceplane. It was launched to low Earth orbit aboard a Falcon 9 rocket from LC-39A on September 7, 2017. Its mission designation is part of the USA series.
 Launch of OTV-5 | |
| Mission type | Classified |
|---|---|
| Operator | U.S. Air Force |
| COSPAR ID | 2017-052A |
| SATCAT no. | 42932 |
| Mission duration | 2 years, 1 month and 20 days |
| Spacecraft properties | |
| Spacecraft type | Boeing X-37B |
| Manufacturer | Boeing |
| Launch mass | 5,400 kg (11,900 lb)[1] |
| Power | Deployable solar array, batteries[1] |
| Start of mission | |
| Launch date | 7 September 2017 |
| Rocket | Falcon 9 |
| Launch site | LC-39A |
| Contractor | SpaceX |
| End of mission | |
| Landing date | 27 October 2019 |
| Landing site | Shuttle Landing Facility |
| Orbital parameters | |
| Reference system | Geocentric |
| Regime | Low Earth |
| Perigee altitude | 355 km (221 mi) |
| Apogee altitude | 356 km (221 mi) |
| Inclination | 54.5 degrees |
The spaceplane was operated by the United States Air Force, 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.[2] Additionally, it was revealed after OTV-5 landed that it had deployed three cubesats in orbit.[3]
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.[4]
OTV-5 was deployed into an orbital inclination of 54.5°, higher than previous X-37B missions. The Air Force has not disclosed the reason for this.[5]
After a record-setting 780 days in orbit, OTV-5 returned to land at the Shuttle Landing Facility on October 27, 2019.[3]
Satellite Deployments
Sometime during its orbital mission, OTV-5 deployed three cubesats, 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.[6] The convention, which the US has ratified, requires newly deployed satellites to be promptly registered with the United Nations Office for Outer Space Affairs.[7]
References
- Krebs, Gunter D. "X-37B OTV 1, 2, 3". Gunter's Space Page. Retrieved 10 July 2013.
- "Air Force preparing to launch fifth Orbital Test Vehicle mission". U.S. Air Force. Retrieved 16 May 2020.
- "USA 295, 296, 297". space.skyrocket.de. Retrieved 16 May 2020.
- Shanklin, Emily (7 September 2017). "OTV-5 Mission". SpaceX. Retrieved 16 May 2020.
- Trevithick, Joseph. "Here's What We Know The Shadowy X-37B Was Up To During Its Record 780 Days In Space". The Drive. Retrieved 16 May 2020.
- McDowell, Jonathan (2 January 2020). "Analysis: Was the X-37B/OTV mission 5 illegal under international law?". Seradata. Retrieved 16 May 2020.
- "Registration Convention". www.unoosa.org. Retrieved 16 May 2020.