| USA-299 | |
| Names List: | Orbital Test Vehicle 6 OTV-6 |
| Mission Type: | U.S. Space Force classified satellite |
| Operator: | United States Space Force |
| Cospar Id: | 2020-029A |
| Satcat: | 45606 |
| Spacecraft Type: | Boeing X-37B |
| Manufacturer: | Boeing |
| Launch Mass: | [1] |
| Power: | Deployable solar array, batteries |
| Launch Date: | 17 May 2020, 13:14:00 UTC |
| Launch Rocket: | Atlas V 501 (AV-081) |
| Launch Site: | Cape Canaveral, SLC-41 |
| Launch Contractor: | United Launch Alliance |
| Landing Date: | 12 November 2022, 10:22 UTC |
| Landing Site: | Shuttle Landing Facility Runway 33 |
| Orbit Reference: | Geocentric orbit |
| Orbit Regime: | Low Earth orbit |
| Orbit Inclination: | 44.60° |
| Apsis: | gee |
| Programme: | OTV program |
| Previous Mission: | OTV-5 |
| Next Mission: | OTV-7 |
USA-299, also referred to as USSF-7 and Orbital Test Vehicle 6 (OTV-6), is the third flight of the first Boeing X-37B, an American unmanned vertical-takeoff, horizontal-landing spaceplane. It was launched to low Earth orbit aboard an Atlas V launch vehicle from SLC-41 on 17 May 2020. Its mission designation is part of the USA series.
The spaceplane is operated by the Department of the Air Force Rapid Capabilities Office[2] and United States Space Force, which considers the mission classified and as such has not revealed the objectives. However an unclassified secondary satellite, FalconSat-8, was deployed from the X-37B soon after launch.[3]
OTV-6 is the third mission for the first X-37B built, and the sixth X-37B mission overall. It flew on an Atlas V in the 501 configuration, and launched from Cape Canaveral Space Launch Complex 41.[4] This flight is the first time the space plane has been equipped with a service module to carry additional pieces for experiments.
OTV-6 was deployed into an orbit with an inclination of approximately 44.60°.[5]
OTV-6 landed after a record-breaking 908 days at the Shuttle Landing Facility on November 12, 2022.[6]
A rideshare payload for the United States Air Force Academy, FalconSat-8, was deployed from the X-37B a few days into the mission. The satellite provides a platform for the academy's Cadet Space Operations Squadron to test various technologies.
Onboard experiments include: