The U.S. military’s X-37B “space plane” is scheduled to launch its sixth mission May 16, carrying multiple defense and civil space experiments aboard, Air Force Secretary Barbara Barrett said May 6.

Speaking during a conference webinar sponsored by the Space Foundation, Barrett said the launch will occur at Cape Canaveral Air Force Station, Florida, in a partnership between the Air Force Rapid Capabilities Offices and the Space Force.

“Demonstrating the department’s innovation, this X-37B mission will host more experiments than any prior missions,” Barrett said. “This launch also demonstrates the department’s collaboration that pushes the boundaries for reusable space systems.”

The Boeing [BA]-made X-37B spacecraft completed its fifth mission in October 2019, landing after 780 days on orbit. The X-37B has spent 2,865 days on orbit, or seven years and 10 months. Its reusability allows the U.S. military to test new systems in space and return them to Earth.

This mission will be the first to include a service module attached to the X-37B to allow for additional experimental payload capability. “This important mission will host more experiments than any prior X-37B flight, including two NASA experiments,” Barrett said.

Among the systems on board are the FalconSat-8, a small satellite developed by the U.S. Air Force Academy and sponsored by the Air Force Research Laboratory with five experimental payloads to be operated on orbit, the service said Wednesday. The two NASA experiments will study the results of radiation and other space effects on a materials sample plate and seeds used to grow food.

Finally, a payload from the Naval Research Laboratory will change solar power into radio frequency microwave energy, which could then be transmitted to the ground, per the Air Force.

“The X-37B team continues to exemplify the kind of lean, agile and forward-leaning technology development we need as a nation in the space domain,” said Space Force Chief of Space Operations, Gen. John “Jay” Raymond in a Wednesday statement. “Each launch represents a significant milestone and advancement in terms of how we build, test, and deploy space capabilities in a rapid and responsive manner.”

Former Air Force Secretary Heather Wilson shared some details about the secretive spaceplane last summer at the 2019 Aspen Security Forum, describing it as similar to a smaller version of the NASA space shuttle, but unmanned.

The X-37B, also called the Orbital Space Vehicle (OTV), can move in an orbit “that looks like an egg and, when it’s close to the Earth, it’s close enough to the atmosphere to turn where it is, which means our adversaries don’t know … where it’s going to come up next,” Wilson said.

As the lines between Air Force and Space Force capabilities continue to be refined, the X-37B remains a Department of the Air Force asset; however, the Space Force is responsible for the launch, on-orbit operations, and landing.

“This launch is a prime example of integrated operations between the Air Force, Space Force, and government-industry partnerships,” said Air Force Chief of Staff Gen. David Goldfein in the Wednesday statement. “The X-37B continues to break barriers in advancing reusable space vehicle technologies and is a significant investment in advancing future space capabilities.”