Testing of the Pratt & Whitney F135 engine has resumed in the Arnold Engineering Development Complex J2 Engine Test Cell at Arnold Air Force Base, Tenn.

The test team is seeking to validate the structural integrity and aerodynamic characteristics of a new fan rotor design for the F135, the powerhouse of the F-35 Joint Strike Fighter Lightning II.

In J2, altitudes up to 75,000 feet can be simulated, along with temperatures from minus 60 to 450 degrees Fahrenheit. Flight speeds of up to Mach 2.6 can also be simulated.

Testing of the engine began in J2 in 2019, but was stopped because of a planned outage to accommodate maintenance. Once that outage concluded, testing resumed with an expectation to continue into early 2021.

“Test results to date have been positive and encouraging, and early results allowed us to complete an AMT (Accelerated Mission Test) with the same newly-designed rotor,” said 2nd Lt. Gregory Landrum, AEDC Jet Engine Test project manager.

“The test team that has been conducting this test has been highly involved and has worked closely with personnel from Pratt & Whitney and the JSF Joint Program Office to frame the desired objectives and collect data toward those objectives.”

The F135 program has conducted more than 5,500 hours of testing in test cells across AEDC.