Watch This: F-35B Fires GAU-22 External Gun Pod in Flight

May 18 2017 - 30 Comments

New Caliber Gun Provides Close Air Support Capability for U.S. Marines.

The U.S. Marine Corps Lockheed Martin F-35B Lightning II Joint Strike Fighter has completed the test firing of its externally mounted General Dynamics GAU-22 25mm gun pod.

The final aerial test firing took place on May 8, 2017 and was conducted by The Salty Dogs of Air Test and Evaluation Squadron (VX) 23’s Integrated Test Force (ITF) at Naval Air Station (NAS) Patuxent River.

Of particular interest in the video just released (that includes footage from several different sorties) is the variety of additional external stores carried on the test F-35Bs. The aircraft are shown with a version of the AIM-9X Sidewinder air-to-air missile and, in a separate flight, with what appears to be a 500lb laser guided bomb possibly a version of the GBU-12 Paveway II.

The new General Dynamics GAU-22 25mm gun pod uses a unique four-barrel configuration that was developed from the highly successful five-barrel, 25mm GAU-12/U gun also built by General Dynamics. The new GAU-22 gun, carried internally on the USAF F-35A variant and in the external pod for the U.S. Marines’ F-35B is and U.S. Navy F-35C is more than 40 pounds lighter and requires 20 percent less overall space than the earlier GAU-12, 5-barrel 25mm gun. The new GAU-22 weapon has a reported rate of fire of “up to 3,300 rounds per minute”. The rate of fire of aerial guns is often reported as “up to…” since the gun can take several seconds to achieve its maximum rate of fire because of the weight of the rotating gun barrels.

The GAU-22A Gun Pod. (Image credit: LM)

The successful in-flight test firing of the 25mm gun pod (started at the end of February), specifically on the U.S. Marine Corps F-35B, somehow addresses questions over the F-35 program’s ability to perform the close air support mission. Several analysts have expressed concern over whether the F-35 is suited for the close air support mission and is a suitable substitute for the CAS-specific A-10 Warthog.

Generally speaking it’s wrong to compare the F-35 with any other asset that was designed to perform a specific mission: the A-10 was built around a unique 30mm cannon nearly as long as the aircraft’s entire fuselage that was intended for the anti-armor close air support (CAS) mission.

While this initial test-firing does not resolve questions surrounding all of the F-35B’s close air support capabilities it is another successful step forward in the program’s progress. At least it can use the gun if called into action during a CAS mission!

The F-35 GAU-22/A gun has been among the most controversial topics: some criticised the fact that the Joint Strike Fighter’s gun can only hold 181 20mm rounds, fewer than the A-10 Thunderbolt’s GAU-8/A Avenger, that can hold some 1,174 30mm rounds.

Moreover, although it was designed with LO (Low Observabity) characteristics, the external pod degrades the F-35’s radar cross section making the 5th generation aircraft more visibile to radars. Still, this should be acceptable for the scenarios where the U.S. Marine Corps F-35B will be called to carry out CAS missions.










  • Paul Rain

    181 20mm rounds, fewer than an F-16 with 500 odd 20mm rounds, fewer than the F-22 with 480 20mm rounds, fewer than the F/A-18 with 410 20mm rounds.

    In other words, it’s garbage.

    • chris mcbride

      In other more educated words it is more accurate and more capable then it’s predecessors.

    • InklingBooks

      Ah, but it’s got the One Ring of invisibility. That’s all that matters. So what if it runs out of ammunition. No one can see it. It can sneak up behind enemy soldiers and go “boo.”

    • Trapperpk

      Does this means the F-35 has 181 wing mounted 20 MM rounds and 181 belly mounted rounds totaling 362, 20 mm rounds on board? The belly gun pod sounds like a plug and play field configuration attribute when the need changes to a CAS environment. The gun pod appears to install on and off with little mechanical effort and will be used as a mission feature for ground attack. F-35 “Good at all things but master of none.” ?

    • chris sullivan

      Couple of points to consider-
      1. 180 is internal cannon capacity, used only on F-35A. This post is about the pod being tested on the F-35B. The pod carries about 20% more shells- 220. The F-35C will also use the gun pod. By the way, F-18 gun capacity is about 575, not 410 rounds.

      2. The 25mm shell is WAY, WAY more powerful than 20mm, don’t let the mere 5mm difference in shell diameter fool you. 1 hit from a 25mm could easily fatally damage a fighter, considering increased blast/frag as compared to 20mm. Try a Google Search of the Apex 25mm round, it might cheer you up to see the ginormous holes & frag damage done to a F-5 test article by a single round.

      3. Before you write off the F-35, you might want to ask how many shells other fighters are carrying these days. Typhoon- 150 27mm, Rafale- 130 30mm, Gripen- about 150 27mm. So, by your logic, the Eurofighter countries (UK, Germany, Italy,Spain), plus France (Rafale) & the Swedes (Gripen) are all morons too. Good to know!

    • Chugs 1984

      So tell me in the thousands of CAS missions completed how many of them used guns, be it the A-10, F-16 or F-18?

      In the last 40 years when was the last time an aircraft flying CAP used its guns compared to missiles?

    • ratherdrive

      Rather useless against armor. Not to mention, it can sometimes take 181 rounds to even “find” the armor, before strikes begin to occur..

    • PikaJew

      It has 30 mm rounds

    • drinking12many

      Most CAS isnt done with a gun and even the A-10s 30MM wont penetrate a lot of modern armor out there.

    • SmoovyBRad

      It’s a 25mm gun, it doesn’t need nearly that much ammo. The difference in weight between a 25mm round and a 20mm is also significant. The MiG-29 (which before you say it is not an air superiority fighter but a tactical multi-role) carries a 30mm cannon with only about 150 rounds, and that is an aircraft heavily used by many forces for CAS, and I don’t think I’ve really heard someone call the -29 “garbage”. For a more “american” comparison, if you will, the A-4 Skyhawk (a dedicated ground attack aircraft) had two 20mm cannons with only 100 rounds each, and that aircraft was designed in the 40’s/50’s and is still in service today, so please, stop.

    • Renato Dallarmi

      But but but.. I am sure they are stealth rounds, tiene Emmy won’t even know they are coming…..

    • stb

      I think F-35 should have 2 engines & an aerodynamic design capable for dogfight maneuverability, beyond stealth capabilities. Then it would become the absolute hit!!!

    • rcerke79

      Fewer than the A-10 with 1350 30mm rounds.

    • Jimmie

      True but the 20mm on any of the 35’s was and is only meant for last ditch air to air defence when a rocket missile etc isn’t feasible or unavailable.

  • billybongo

    I see that the aircraft is coal-fired from the smoke puffs, heating up the steam-driven engine. The enemy is frightened by the sound of a train whistle going “Choo Choo!”

  • Särimner

    A multi-multimillion dollar stealth-fighter performing CAS. In broad daylight or even at night at close range. How do you think???

  • ScoobiJohn

    181 rounds is kinda pathetic – though i expect since the f-35 is supposed to do ‘close’ air support from high altitude with guided munitions suppose it will rarely get used – what this gun needs is laser guided bullets – if every bullet was a guaranteed hit wouldn’t be so bad – but dont know if they are even close to being past prototype stage

  • Andrew Tubbiolo

    Why have the gatling gun if the pod can only hold 181 rounds? To add to that question it looks like they’ve set the firing rate to a very low speed taking away the benefits of a gatling type gun. Better off going to a cannon and then you could hold more rounds in the enclosure. Maybe they wanted the choice of fast or slow rate, but with that small magazine of rounds, that system better not miss.

  • toady

    I think you’re being unfair about the benefits: compromising stealth; increased drag; pylon flexing reducing targeting accuracy; and extra airplane weight to engineer that hard-point to that flush pylon.

    But none of those benefits matter because Lockheed hit a design milestone.

  • Ilya Kurenkov

    Gun pod on a stealth plane.. I hope, that F-35 case will be included to all aeroengineering studybooks as a perfect example of how combat plane should not be developed. All and every mistakes were done, and tons more are still to come.

  • Rob Annable

    A rate of fire (up to) 3300 per minute means (up to) 55 rounds per second. So with a capacity of 181 rounds, it can carry enough for just over 3 seconds of shooting. *slow claps*

    (unless my maths is massively wrong)

  • Cocidius

    Bravo USMC! It’s only taken 16 years of development and $500 billions dollars of funding to duplicate an operational capability that every other aircraft tasked with CAS has been able to do for the last 50 years.

  • Black Eagle

    Wow, that gun is so stealth that it doesn’t even make any noise.

  • JMurman

    The limited amount of ammo carried versus the huge monies invested should be a non starter to any thinking person. However we are not talkingn about a rational thinking person, but a political football that both military complex and politicians are drooling over.

    • Ilya Kurenkov

      Please be sure there are very, very rational thinking people behind this project. You just have to look at F-35 from another angle. This is absolutely brilliant project, aimed for making money. Lockheed Martin earns tons of bucks of F-35, employ thousands of people and shows excellent financial results year by year. The only thing they have to do is to continue development of F-35, the longer the better. They are simply not interested in finishing this project.
      So this is just a matter of priorities: you expect to receive capable combat aircraft, LM expect good financial reports in years to come.

      • Uniform223

        “The only thing they have to do is to continue development of F-35, the longer the better. They are simply not interested in finishing this project.”

        > oh you mean like Sukhoi’s PAKFA project? How many aircraft do they have? 9? After 17 years of advertising, rhetoric, and propaganda all they have to show for are 9 aircraft and one with a new paint job. *slow clap, slow clap*

  • cromicacid

    Only the F-35A has an internal gun. Only has 180 25mm rounds……just enough for maybe 3 second squeeze on the trigger.

  • WpnsLoader175

    I am still waiting for my brass from these shoots. Weather was nice and was a good distraction from normal to go out to there and hand crank ammo in. This has just enough ammo for one good gun run, not going to help much in CAS. A-10 fires 100-300 rounds, depending on requirements of the fight, of much larger 30mm HEI rounds. However the 20mm rounds are next to useless, so at least the few bullets it does have are halfway descent.

    • Uniform223

      1 250lbs guided HE multifunction (airburst, impact, and penetrating) guided munition that can be accurate within 1 meter, is more effective then 100 rounds of 30mm HEI rounds. The 25mm for the F-35 that will most likely be computer controlled is said to be more accurate then the former and fires armor piercing explosive rounds. A 25 or 50 round burst would give any soft or lightly armored target a bad day. In either case I wouldn’t want to be on the receiving end of either of them.

  • Uniform223

    The AV-8B Harrier is the primary fixed wing CAS aircraft for the USMC and it uses a 25mm gun pod and doesnt have that many rounds over the GAU-22A of the F-35. I dont hear people complaining about the Harrier or the FACT that all variants of the F-35 carries more bullets then any European or Russian fighter aircraft.