The Air Force is funding the construction of new wind tunnels for hypersonic testing, with new sites in development at two Indiana universities and an additional tunnel being built at Arnold Air Force Base, Tenn.

Air Force Secretary Heather Wilson told the House Armed Services Committee April 2 that the service will be building new wind tunnels in response to a query from HASC member Rep. Scott Desjarlais (R-Tenn.) on her assessment of the service’s capability to test hypersonic weapons.

Brig. Gen. Christopher Azzano, commander of the Air Force Test Center, right front, tours the Aerodynamic & Propulsion Test Unit at Arnold Air Force Base on Nov. 16. The facility tour was led by AEDC Hypersonic Systems Combined Test Force Director Lance Baxter, who is on Azzano’s right. Azzano and other AFTC leadership visited Arnold Air Force Base in mid-November to take part in the 2018 AFTC Strategic Offsite, Azzano’s first offsite since assuming the role of AFTC commander in August. (U.S. Air Force photo by Brad Hicks)

“We are actually going to be building more hypersonic wind tunnels, … one in Indiana and another at Arnold,” Wilson said. “Overall … there is a significant investment in the Air Force budget in improving our testing and training ranges.”

Specifically, the service is funding the construction of new quiet wind tunnels at Purdue University and the University of Notre Dame, both in Indiana, said Air Force Public Affairs Officer Capt. Cara Bousie in an April 18 email to Defense Daily.

A quiet wind tunnel is one designed to minimize freestream disturbances and yield more accurate aerothermodynamics predictions. Two quiet hypersonic wind tunnels currently reside at Texas A&M University and at Purdue. The new tunnels are slated to be twice the diameter of these existing sites, and are being funded through congressional adds from fiscal years 2018 and 2019, Bousie said.

The University of Notre Dame recently completed construction of its new Mach 6 quiet wind tunnel, according to a November 2018 press release. The $5.4 million project was funded with support from the Air Force Office of Scientific Research, the Office of Naval Research, Boeing [BA], Notre Dame’s College of Engineering and Notre Dame Research, the university said.

The Air Force is also building a second large-scale wind tunnel at the Arnold Engineering Development Complex (AEDC) at Arnold AFB. In fiscal year 2017, the Office of the Secretary of Defense Test Resource Management Center (TRMC) – part of the Under Secretary of Defense for Research and Engineering – began a $281.5 million hypersonic wind tunnel construction project there, Bousie said in the email. “TRMC’s investment will culminate in the completion of a large-scale Mach 7+ variable speed wind tunnel in 2023,” she said.

This new tunnel will support hypersonic testing across the Defense Department, Bousie noted. As far as the Air Force’s two current hypersonic weapons programs go, the Lockheed Martin [LMT]-led Advanced Rapid Response Weapon (ARRW) program is using current Air Force hypersonic facilities at AEDC to meet its schedule, while the Hypersonic Conventional Strike Weapon (HCSW) program, also led by Lockheed, is scheduled to use existing AEDC facilities beginning in the first quarter of FY ’20.

Thus far, both programs remain on schedule to reach early operational capability as planned in FY ’22, Bousie said. Air Force officials previously said that first flight for each system could occur between the end of 2020 and mid-2021 (Defense Daily, Feb. 8).

“Upon completion of the Department’s wind tunnel investment, the Air Force will sustain the wind tunnel just as it does other ground test capabilities within the Major Range and Test Facility Base,” Bousie said.