A Tale of Two Gatling Guns: F-35 vs. A-10

The Daily Beast's Dave Majumdar is out with another excellent story about how the gun on the F-35 Joint Strike Fighter, the Pentagon's newest and most expensive fighter jet, won't work for another four years -- at the earliest.

That's because the software that lets pilots shoot the Gatling gun, which is critical for the aircraft to provide close-air support to ground troops, isn't expected to ship until 2019, according to the article.

As Majumdar writes:

"There will be no gun until [the Joint Strike Fighter’s Block] 3F [software], there is no software to support it now or for the next four-ish years," said one Air Force official affiliated with the F-35 program. "Block 3F is slated for release in 2019, but who knows how much that will slip?"

What's also interesting to note is how few rounds the General Dynamics Corp.-made weapon actually holds compared to the 1970s-era A-10 Thunderbolt II.

The GAU-22/A, a four-barrel version of the 25mm GAU-12/U Equalizer rotary cannon found on the Marine Corps' AV-8B Harrier II jump set, is designed to be internally mounted on the Air Force's F-35A version of the aircraft and hold 182 rounds. It's slated to be externally mounted on the Marine Corps' F-35B jump-jet variant and the Navy's F-35C aircraft carrier version and hold 220 rounds.

The GAU-22/A is lighter and more accurate than its predecessor, but with a reduced rate of fire of 3,300 rounds per minute. At that rate, the F-35 would be out of ammunition in about four seconds, or one or two bursts of fire.

By comparison, the 30mm, seven-barrel GAU-8/A Avenger in the nose of the venerable Warthog attack aircraft can hold as many as 1,174 rounds. It's configured to fire at a fixed rate of fire of 3,900 rounds per minute.

The F-35, in its full configuration with the Block 3F software, is designed to carry a suite of internal and external weapons, including the GPS-guided Joint Direct Attack Munition, laser-guided Paveway II bomb, Advanced Medium-Range Air-to-Air Missile and infrared Sidewinder missile.

Still, the long wait for a functional F-35 gun is likely to raise more questions about the Air Force's repeated push to send the A-10 to the bone yard. Lawmakers disagreed with the service's fiscal 2015 budget proposal to retire the aircraft and authorized funding to keep the plane flying for at least another year.

Even war commanders seem sold on the merits of the A-10, which was deployed to Iraq in recent months to help U.S. and Iraqi forces fight Islamic militants. Video of the planes firing its iconic gun at suspected ISIS targets has circulated online.

Meanwhile, the Pentagon plans to begin operational flights of the F-35 -- even without the use of the gun and lingering concerns over software -- this year. The F-35B is slated to reach so-called initial operational capability by the end of the year, the F-35A by late next year and the F-35C by February 2019.