Lockheed Martin test pilot Dan Canin flew the 12th “weight-optimized” F-35 Lightning II test airframe on May 21, completing the allotted trials batch. CF-3, the third of the F-35C carrier versions, is now undergoing initial trials before joining two other F-35Cs and four F-35B STOVL test aircraft at Naval Air Station Patuxent River, Md., later this year. On the same day, the F-35 made its first public display with a flypast by CF-2 at Andrews Air Force Base, Md.

The “weight-optimized” aircraft (four F-35As, five F-35Bs and three F-35Cs) were preceded by a single prototype, AA-1, which first flew on Dec.15, 2006. It was flown 91 times before being grounded in December 2009, and is now being used for live-fire testing. The first of the aircraft with production-representative airframes, BF-1, took to the skies in June 2008.

First flight dates of the trials batch are as follows:

• BF-1: June 11, 2008

• BF-2: Feb. 25, 2009

• AF-1: Nov. 14, 2009

• BF-3: Feb. 2, 2010

• BF-4: April 7, 2010

• AF-2: April 20, 2010

• CF-1: June 6, 2010

• AF-3: July 6, 2010

• AF-4: Dec. 30, 2010

• BF-5: Jan. 27, 2011

• CF-2: April 29, 2011

• CF-3: May 21, 2011

CF-3’s inaugural flight occurred the same month the Air Force formally accepted the first two low-rate initial production F-35s, with AF-7 delivered to Edwards AFB, Calif., on May 6 and AF-6 on May 12.