WASHINGTON — For the first time, a US Air Force F-35 fighter jet has successfully fired its internal gun from the air.

The aerial gun test marks another milestone in the Pentagon's effort to certify the F-35A's internal 25mm Gatling gun. The Joint Program Office Lockheed Martin released a video Monday of F-35 test pilot Maj. Charles "Flak" Trickey firing the first aerial gun burst from the four-barrel weapon.

First F-35 In Flight Gun Fire

First F-35 In Flight Gun Fire. Video by Lockheed Martin Corporation

The F-35A completed the test during an Oct. 30 flight at Edwards Air Force Base, California, the JPO announced in a joint statement Monday. This was the first in a series of flight tests to evaluate the in-flight operation of the plane's internal gun.

This is the second phase of F-35 gun testing, which will assess the gun's performance and integration with the airframe while the plane is airborne. The first phase of the test period consisted of 13 gunfire events with the plane on the ground over the course of three months, which verified the integration of the gun into the plane.

The gun system will be tested further next year with a production F-35A for integration with the jet's full mission systems capabilities, according to the JPO. The test team will demonstrate the gun's effectiveness in both air-to-air and air-to-ground employment.

The F-35 gun will be operational in 2017, at the end of the program's system development and demonstration phase, the JPO said.

"The successful aerial gun test sortie was a culmination of several years' planning, which intensified in the first half of 2015 at the Edwards F-35 Integrated Test Force (ITF) Flight Test Squadron with a team of Air Force, Lockheed Martin, Pratt & Whitney, General Dynamics, and Northrop Grumman personnel," said Mike Glass, Edwards ITF flight test director, according to the statement. "The results of this testing will be used in future blocks of testing, where the accuracy and mission effectiveness capabilities will be evaluated."

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