Lockheed Martin [LMT] and the F-35 program recorded a handful of software-related milestones in August, according to a company statement.

The Marine F-35B short takeoff and vertical landing (STOVL) variant aircraft BF-1 and BF-4 completed “Mode 4” formation testing Aug. 9, as required for software block 2B capability. J.D. McFarlan, Lockheed Martin vice president for F-35 test and verification, said in a statement, in Mode 4 operations, the STOVL propulsion system is engaged with the lift fan, roll-post nozzle and three-bearing swivel nozzle operating. All propulsion doors and inlets are also open while running in Mode 4 operations, McFarlan said.

The Marine Corps' F-35B. Photo: Lockheed Martin.
The Marine Corps’ F-35B. Photo: Lockheed Martin.

Flight testing, McFarlan said, validated the F-35B variant’s ability to operate well in this configuration during formation flight, which supports operations around the ship. This is a key milestone for the F-35B path to initial operational capability (IOC), McFarlan said.

F-35B aircraft BF-3 completed block 2B software fleet release weapon separation requirements for the B-variant with two successful AIM-120 Advanced Medium Range Air-to-Air Missile (AMRAAM) air vehicle instrumented (AAVI) separation flights on consecutive days, Aug. 14 and 15. McFarland said block 2B software release is critical because it delivers the first combat capability to the F-35. The AMRAAM is developed by

Raytheon [RTN].

Lockheed Martin spokesman Eric Schnaible said Monday the F-35B’s IOC goal is the second half of 2015.

The F-35 program also tallied a pair flight test milestones this month. F-35A aircraft AF-1 accomplished its 400th flight during a successful GBU-31 Joint Direct Attack Munition (JDAM) aircraft separation test Aug. 13, which Lockheed Martin said also marked the first time a GBU-31 Mark-84 separation was demonstrated from the F-35. Previous GBU-31 separations were with the BLU-109 (bomb live unit) bomb body. Lockheed Martin said GBU-31 Mark-84 is the 2,000-pound guided munition class. JDAM is developed by Boeing [BA].

The overall system development and demonstration (SDD) F-35A test fleet surpassed its 4,000th flight hour Aug. 14, and, in total, the F-35 fleet has surpassed 19,500 flight hours, with more than 8,000 hours in SDD aircraft. F-35A aircraft AF-1 achieved its 400th flight milestone on Aug. 13; F-35A aircraft AF-4 surpassed 500 flight hours on Aug. 11, while F-35C aircraft CF-2 achieved 300 flights on Aug. 14.

The F-35 is developed by Lockheed Martin with subcontractors BAE Systems and Northrop Grumman [NOC]. The F135 engine is developed by Pratt & Whitney of United Technologies Corp. [UTX]