Leonard David's INSIDE OUTER SPACE

OTV-6: On the ground at Kennedy Space Center in Florida.
Image credit: Staff Sgt. Adam Shanks

After spending 908 days in Earth orbit, the sixth mission of the U.S. military’s X-37B Orbital Test Vehicle-6 (OTV-6) has come to wheels-stopped at NASA’s Kennedy Space Center Shuttle Landing Facility.

This Boeing-built vehicle was launched on May 17, 2020 from Cape Canaveral Air Force Station, Florida.

Coasting in for a landing on November 12 at 5:22 AM local Florida Time, the robotic OTV-6 was the first mission to introduce a service module – a ring attached to the rear of the vehicle. That module expanded the number of experiments that can be hosted during a space plane mission.

Artwork depicts X-37B in Earth orbit.
Credit: Boeing

The service module successfully separated from the OTV prior to landing. In the coming weeks, the service module will be disposed of in accordance with best practices, according to a U.S. Space Force statement.

Secretary of the Air Force Frank Kendall said: “The deliberate manner in which we conduct on­orbit 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.”

OTV-6 image credit: Staff Sgt. Adam Shanks

Some payloads identified

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, transforming that energy into radio frequency microwave energy.

Additionally, the U.S. 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 toted 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, according to the U.S. Space Force statement.

OTV-6 image credit: Staff Sgt. Adam Shanks

Another NASA experiment investigated 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.

Boundaries of experimentation

“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, Department of Air Force 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,” Fritschen said in the U.S. Space Force statement.

Commemorative mission coin might be showing the X-37B “service module.”
Courtesy: Mike Rose

Flight roster

OTV-1: launched on April 22, 2010 and landed on December 3, 2010, spending over 224 days on orbit.

OTV-2: launched on March 5, 2011 and landed on June 16, 2012, spending over 468 days on orbit.

OTV-3: launched on December 11, 2012 and landed on October 17, 2014, spending over 674 days on-orbit.

OTV-4: launched on May 20, 2015 and landed on May 7, 2015, spending nearly 718 days on-orbit.

OTV-5: launched on September 7, 2017 and landed on October 27, 2019, spending nearly 780 days on-orbit.

Shattered records

X-37B hangar at Kennedy Space Center.
Credit: Michael Martin/SAF

With the successful completion of its sixth mission the reusable space plane has now flown over 1.3 billion miles and spent a total of 3,774 days in space where it conducts experiments for government and industry partners with the ability to return them to Earth for evaluation, added a Boeing statement on the landing.

“Since the X-37B’s first launch in 2010, it has shattered records and provided our nation with an unrivaled capability to rapidly test and integrate new space technologies,” said Jim Chilton, senior vice president, Boeing Space and Launch.

“With the service module added, this was the most we’ve ever carried to orbit on the X-37B and we’re proud to have been able to prove out this new and flexible capability for the government and its industry partners,” Chilton said.

The X-37B program is a partnership between the U.S Department of the Air Force Rapid Capabilities Office and the U.S. Space Force. Boeing designed and manufactured the space plane and continues to provide program management, engineering, test and mission support from sites in Southern California, Florida and Virginia.