Lockheed Martin hopes to make headway with the “maturity” flights of the F-35 Joint Strike Fighter at Edwards AFB, Calif., now that AF-6, the second of two test aircraft at Edwards, was expected to conduct its first maturity flight as soon as July 12.

Maturity flight testing for AF-6 and AF-7 is one of a series of steps for the Joint Strike Fighter program prior to entering pilot training as planned this fall. The goal is to fly the Block 1A software, which includes mission avionics, basic navigation and instrumentation and some radar and electronic warfare systems, on these two aircraft prior to clearing it for pilot training at Eglin AFB, Fla.

The maturity flight-test phase was added by the Pentagon as part of the significant program restructuring this year designed to reduce developmental risk.

The Block 1A software package is not suitable for actual combat, but it is the configuration that will be used for initial pilot training.

Lockheed Martin spokeswoman Laurie Quincy says that AF-6 is slated to make its first Block 1A flight on July 12. To date, this aircraft has been flying Block 1 software as part of the developmental testing program.

AF-7, by contrast, has flown five “maturity” tests to date, Quincy says. They include one focused on software regression work and four flights designed to work through the training syllabus. These maturity flights, in part, are designed to ensure the aircraft can support the syllabus coursework needed to train the pilots.

Included in these four flights were basic assessments of the aircraft (including handling, pattern work and instrumented approaches/landings). During the software regression flight, the pilot executed previously flown maneuvers using the updated software.

Once the maturity testing is complete, the focus will turn to clearing AF-8-13 for flight at Eglin.

Prior to starting formal training in the fall, the Pentagon has slated a two-month operational utility evaluation. During this phase, professional testers from the Air Force and Navy will evaluate the aircraft’s readiness for formal training.

AF-8-12 have each conducted their first flights; first flight for AF-13 is planned soon. None of the aircraft have yet to be delivered, however, to Eglin.

“Unlike the F-35 aircraft in the system development and demonstration phase of the program, AF-8 and AF-9 are in a production configuration and are not monitored by flight-test instrumentation during flight,” Quincy says. The company and government are “proceeding cautiously through extensive reviews of test data and documentation to finalize the aircraft delivery. We need to be certain the jets are ready for an operational environment and these reviews are taking a little more time than anticipated.”