X-37B Orbital Test Vehicle-6 was the first mission to introduce a service module-a ring attached to the rear of the vehicle expanding the number of experiments that can be hosted during a mission.
The X-37B Orbital Test Vehicle-6 (OTV-6), the US Space Force’s unmanned, reusable spaceplane, successfully deorbited and landed at NASA’s Kennedy Space Center Shuttle Landing Facility on Nov. 12, 2022, at 05:22 a.m.
According to a US Space Force news release, OTV -6 was the first mission to introduce a service module-a ring attached to the rear of the vehicle expanding the number of experiments that can be hosted during a mission. “This mission highlights the Space Force’s focus on collaboration in space exploration and expanding low-cost access to space for our partners, within and outside of the Department of the Air Force (DAF),” said Gen. Chance Saltzman, Chief of Space Operations.
The service module successfully separated from the OTV before landing, which is a necessary activity due to the aerodynamic forces experienced by the X-37B vehicle upon re-entry. In the coming weeks, the service module will be disposed of in accordance with best practices. Secretary of the Air Force Frank Kendall said, “The deliberate manner in which we conduct on¬orbit operations-to include the service module disposal-speaks to the United States’ commitment to safe and responsible space practices, particularly as the issue of growing orbital debris threatens to impact global space operations.”
The OTV-6 mission hosted the Naval Research Laboratory’s Photovoltaic Radiofrequency Antenna Module. This experiment successfully harnessed solar rays outside of Earth’s atmosphere and aimed to transmit power to the ground in the form of radio frequency microwave energy. Additionally, the US Air Force Academy’s FalconSat-8, developed in partnership with Air Force Research Laboratory, was successfully deployed in October 2021. FalconSat-8 remains in orbit, providing Academy cadets unique hands-on experience as space operators prior to entering active duty.
Multiple NASA experiments were deployed on OTV-6. The Materials Exposure and Technology Innovation in Space (METIS-2) included thermal control coatings, printed electronic materials, and candidate radiation shielding materials. METIS-1-which flew on OTV-5-consisted of similar sample plates mounted on the flight vehicle. NASA scientists will leverage data collected after the materials have spent 900+ days in orbit and compare observed effects to ground simulations, validating and improving the precision of space environment models.
Another NASA experiment aims to investigate the effect of long-duration space exposure on seeds. Scientists are interested in the seeds’ resistance and susceptibility to space environment-unique stresses, notably radiation. The seeds experiment will inform space crop production for future interplanetary missions and the establishment of permanently inhabited bases in space.
“The X-37B continues to push the boundaries of experimentation, enabled by an elite government and industry team behind the scenes,” said Lt. Col. Joseph Fritschen, DAF Rapid Capabilities Office’s X-37B Program Director. “The ability to conduct on-orbit experiments and bring them home safely for in-depth analysis on the ground has proven valuable for the Department of the Air Force and scientific community. The addition of the service module on OTV-6 allowed us to host more experiments than ever before.”
The sixth mission conducted on-orbit experiments for 908 days. OTV-6, was launched on May 17, 2020 from Cape Canaveral on an Atlas V.
Before OTV-6, the US Air Force (USAF) successfully flown five X-37B missions, OTV-1 through OTV-5. All five missions launched from Cape Canaveral Air Force Station, Fla., beginning with its first launch on Apr. 22, 2010. OTV-1 through OTV-3 all landed at Vandenberg Air Force Base (AFB), Calif., while OTV-4 and OTV-5 landed at Kennedy Space Center, Fla. Through five completed missions, the X-37B has spent a total of 2,865 days on orbit, successfully checking out the X-37B’s reusable flight, reentry and landing technologies as well as operating experiments to benefit the national space community.
The X-37B Orbital Test Vehicle, or OTV, is an experimental test program to demonstrate technologies for a reliable, reusable, unmanned space test platform. 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.
Photo credit: Staff Sgt. Adam Shanks / U.S. Air Force