WW2 Aircraft Weapons 50 cal. Vs The World

Just after World War Two the U.S. moved forward with the "Optimal Caliber Program". This was an effort to determine just what would be the best caliber of weapon to use for air to air combat. This report gives us a lot of data, not only on the weapons used, but on the effects of damage to various airplanes.
Let's talk about it and take a look at the data provided.
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[@seanbarron5231]

Nothing better than “Greetings, this is Greg”

[@BlueBaron3339]

Agreed! And kudos for not saying "First!" 😂

[@huwzebediahthomas9193]

The first man on the bluddy moon...

[@LEGOBubuS]

❤❤❤

[@shuritgaming8038]

“Let’s get this out on a tray “ Nice “

[@dukecraig2402]

The two best intros for KZbin videos are; "Greetings this is Greg" And "The intent of this video..."

[@damage6316]

As a former USMC machine gunner, career infantryman, and current full time firearms design engineer I can confirm you are absolutely spot on w/ the comments concerning the M2 sustained fire performance. 20 second burst on the ground is a bit harsh but with a hundred knots of slipstream blowing on the gun it's not a problem at all.

[@kylegoldston]

Also the M2 is open bolt, So there's 150-200kn cooling air flowing through the .50" / 12.7mm bore, around the belted .50cal round and slamming into the breech face cooling the entire Inside of the receiver.

[@danphariss133]

@@kylegoldstonIts not open bolt its a closed bolt MG. All the Brownings were.

[@danphariss133]

And the M2 HB will shoot several 100 round “bursts” in succession. In just a few minutes. This from watching a Quad 50 in VN. The would put a 100 round box in each gun and run them dry. Then repeat maybe 4 times shooting azimuths even into North Vietnam if the elevation was high. Con Thien was only about 1.5 clicks from the “pink line”.

[@georgewashington92]

Greg, my family lived through ww2 in occupied Luxembourg, they witnessed a lot of strafing attacks, factory close to their home, german truck columns, trains etc. Still got some empty shells they picked up. They always said, when the .50 opened up, it was hell on earth, like a giant lightning destroying everything in it's past. My grandfather witnessed a P47 strafing a train, boiler penetrated and exploded, crew boiled alive.

[@johnsledge3942]

I see hour-long lectures and I often wince at the thought, but a 1 hour Greg video is always a treat! Excellent work as always.

[@scylex47]

My feelings exactly

[@stephencastello6553]

If he made a 24 hour video lecture I would gladly sit and listen.

[@JP-su8bp]

Perhaps there is a difference between an hour-long lecture and an hour-long exploration.

[@EricTheBlue2010]

Facts. His videos are always so dense and his use of primary sources from the era always fascinates me

[@LexieAssassin]

Have you heard of our lord and savior, Perun then, by chance?

[@nickmitsialis]

RE: the MK 108, it was also kind of dangerous to use due to the extreme destructive power: I recall reading in the Helmut Lipfert War Diary that he used the 30mm on a Sturmovik, the aircraft just literally blew apart, and he very nearly got taken down by the large pieces of debris (engine block, the back half of the fuselage the wings) that unexpectedly flew back at him. Later he learned to get in close and break hard after shooting, but he did mention it was hard to use on a single engine fighter that was maneuvering.

[@nickradner5325]

I’ll admit. I’m started watching Greg’s channel a few weeks ago. Totally and completely lost most of the time, but fascinated. You give it a few binge watches. And everything starts to make sense. One of the MOST intriguing channels I’ve ever seen. Good stuff man

[@JohnDiabol]

Considering that the Mk-108 essentially spits out what has the equivalent explosive force of a hand grenade and it does this up to 10 times a second, it's no wonder it was a devastatingly effective weapon.

[@skittlesbutwithchocolatein2274]

some could argue the ballistics but pilots fired at close range anyway

[@killer.crayon]

With quite a low ballistics, MK 108 demanded the interceptor to approach to a knife-fight distance of 100m to hope the hit statistics will satisfy your commanders. While itchy-trigger-fingers on buffs started to fill the sky with bullets at 1000m. Therefore, to deliver a push, an MK 108 owner must have a sturdy armour and steel balls. That's why Fw 190 A-8/R8 had heavy frontal armour along with those 30mm cannons. Trying to catch an enemy fighter with low ballistics MK 108 could be even harder than approaching an actively defending bomber. No. MK 108 is just a grenade launcher in the sky.

[@JohnDiabol]

@@killer.crayon you didn't watch the video, did you? Like Greg clearly states, most aerial engagements took place at ranges of 300 yards or less and thus the low velocity of the 30mm was largely irrelevant in most combat situations.

[@Crosshair84]

@@JohnDiabol The low muzzle velocity of the 30mm was most certainly NOT irrelevant and a limiting factor of the design. Even at a range of only 100 yards, a 30mm shell takes, with no air resistance, .1875 seconds to reach the target. At 200 yards, the pilot has to lead their target at least a third of a second in advance. 300 yards is half a second. This isn't even considering bullet drop, which is significant once you get much past 100 yards at such a velocity. The 30mm has the ballistics akin to that of a 12 gauge shotgun slug. Which is why even with the development of radar gunsights, no country chose to use weapons with such a low muzzle velocity. By comparison, the WW2 MG 151 has a muzzle velocity 50% greater and the M2 Browning 300 fps faster than the 20mm. Resulting in less lead and less drop compensation being needed. Post war, the ADEN cannon was developed. It has double the muzzle velocity of the MK108.

[@JohnDiabol]

@@Crosshair84 I said that it was largely irrelevant in most actual real life combat scenarios at 300 yards or less. An experienced pilot will know the appropriate lead and he only needs to get lucky once in order to swat down a Mustang or a Thunderbolt. Post-war weapons had double the muzzle velocity because aircraft had also almost doubled in speed with the jet age.

[@rayschoch5882]

Excellent, as usual, Greg. My Dad's experience with the P&W R-2800 in two different F6F's supports the notion that a single hit to the engine won't necessarily be fatal to the airplane's longevity. One plane took a 20mm to the prop hub, which drained most (but not quite all) of the oil. It ran for 250 miles to get him back to the carrier safely. The other plane took a 40mm hit to the engine (plus some other hits) but lasted long enough to get him back to the carrier to land safely.

[@vvvci]

In the previous video, Greg said that a cylinder shot off would lead to oil loss immediately, and therefore the motor would SEIZE UP shortly. But I've read and seen videos of many pilot accounts saying that they got their P&W R2800 powered fighters home safely after exactly those types of direct hits on the engine

[@davidelliott5843]

It probably depends which cylinder gets blown off. Lower cylinders will dump the oil pretty fast. Upper cylinders will cover the windshield in oil. Side pots won’t lose oil as fast as the bottom four and the spray should miss the cockpit.

[@vince_cb]

Correct me if I’m wrong but 20s was from a single gun. For a P47 (8 M2s) that emulates a 2.5 second burst on target, and for a P51 it emulates a 3.33s burst.

[@GregsAirplanesandAutomobiles]

That's exactly correct.

[@killer.crayon]

425 rounds per gun with 800rpm (13.33333 Hz) results in 31 seconds of continuous burst. On the other hand, P-51D had 270rds+270rds+400rds+400rds+270rds+270rds for its guns, giving 20 seconds of full 6-gun burst, plus 9 seconds more of 2-guns burst. However, with 113 grams per cartridge, 8*425rpg*113g=384kg of ammo, P-47 pilots often tried to avoid this load. Popular ammo layout for P-47 is 3*200rpg+2*300rpg+3*200rpg. 15 seconds of 8-guns burst, plus extra 7 seconds of 2-guns burst.

[@karlbrundage7472]

@<a href="#" class="seekto" data-time="2269">37:49</a>- Regarding damage from explosive shells, it's a point that the 20mmHE fired from the license-built Oerlikons in the A6M and other Japanese aircraft had increased bursting charges, but reduced casings, making the shells burst immediately upon contact with the airframe. That caused more explosive damage, but decreased damage from shell splinters, which ultimately cause A and B damage.

[@GARDENER42]

Note the 30mm ADEN had a 1,200-1,500 rpm fire rate, later increased to 1,500-1700. Considering the Hunter carried four, I think this was sufficient... I worked on these on the Lightning in the 1970s. Dismounted test firing was awesome. 😁

[@20chocsaday]

At Lightning speed they would need a good aiming system. Fortunately they didn't have to prove it to an enemy. But you must have learned a lot working on them which the world does not need to know. Thank you for helping us.

[@CJB-]

Greg wont like this as he's nationalistic.

[@davidelliott5843]

Lightning was fast, short range and carried a big punch. If it failed to stop a nuke bomber, a second attempt was irrelevant. Due to the distances involved, an issue the USAF never needed to worry about.

[@CAL1MBO]

It's 1500rpm for the gunpack, NOT 4x 1500rpm. In case anyone was confused.

[@GARDENER42]

@@CAL1MBO No, you're mistaken; that's per GUN.

[@icewaterslim7260]

Japanese IJN Ace Honda Minoru said in an interview that he would've liked to have had our "Browning .50 calibers and more horsepower". He described the relatively low velocity 20 mm type 99 canon round in the A6M as "dropping like a stream of piss." Claiming to be the worst shot in his flight school, his practice with a 6 o'clock approach was to close to within under 50 meters and sweep 20 mm across his adversary to avoid the debris. Actually not really much different than the gunnery practices of Richard Bong and Erich Hartmann.

[@GregsAirplanesandAutomobiles]

Yes, in fact quite a few WW2 aces were believers in shooting at very close range. High scoring aces that fired from longer ranges were the exception not the rule.

[@icewaterslim7260]

@@GregsAirplanesandAutomobiles IIf I remember correctly Charles MacDonald was known as a deflection shooter. He was with the Aces Loaded 475th out of New Guinea then the Philippines and did a stint as their Commander.. They were frequent escorts for the Third Attack Group's Parafrag Squadrons. My Dad Got into the Pacific relatively late as an A20 and A26 Gunner who claimed he never got to shoot at much, if anything, because those P38s wouldn't let anything near him. He actually thought the world of those guys.

[@Teh0X]

Oerlikon FF derivates; MG FF and Type 99 Mark 1 were pretty much the minimum you'd consider a cannon instead of grenade launcher due to their velocity. Simply weight saving gone too far.

[@DIREWOLFx75]

"He described the relatively low velocity 20 mm type 99 canon round in the A6M as "dropping like a stream of piss."" The Type 99-1 had a V0 of 600 m/s. In comparison, the German 30mm mk 108 had a V0 of 540 m/s. And the Type 99-2 had a V0 of 750 m/s. Extremely worth also keeping in mind is the fact that the original Type 99-1 was 5kg lighter than the airforce Browning .50. While the later Type 99-2 weighed roughly 10kg more than the airforce .50. You choose your tradeoffs.

[@vvvci]

@@icewaterslim7260 - I think that might be the P-38 pilot I mention in my above retelling of a long-range triple shoot-down over PIs

[@dukecraig2402]

Yes, the German MK 103 and the MK 108 cannons fired the same projectile in regards to the 330 gram HE (High Explosive) projectile, the higher velocity MK 103 also fired an armor piercing projectile which would have been pointless to load for the MK 108 with it's much lower muzzle velocity. The MK 103 was chambered for a 184mm casing which was just over twice as long as the MK 108's chambering which had a 90mm casing. But that's not the only reason that the MK 103 had such a higher muzzle velocity of 2,800 fps vs the MK 108's muzzle velocity of 1,770 firing the same 330 gram projectile, it's also because the MK 103 has a barrel length at 52.7 inches that's almost twice as long as the MK 108's at 23 inches, all other things being equal and a longer barrel alone gives higher muzzle velocity. Given that the cartridge casing is twice as long and the barrel length is twice as long on the MK 103 as they are in the MK 108 I'm surprised that the same projectile isn't even faster coming out of the MK 103 than what it is, all that said it's the 355 gram armor piercing round fired from the MK 103 is why they did what they did to get that kind of muzzle velocity out of it, as you surmised it wasn't intended for knocking down aircraft it's a tank buster gun, it's AP rounds were capable of penetrating up to 2 inches at a 60° hit and 3.7 inches at a 90° hit which would take care of a lot of armored vehicles in WW2 especially when you consider that attacking aircraft hit armored vehicles from the top where armor is the thinnest especially around the engine compartment. Wherein explosive ammo task with destroying aircraft doesn't need a lot of velocity for the sake of penetrating armor especially 30mm cannons, they would explode entering the skin overpressurizing the inside of the fuselage or wing of an aircraft and blow it out tearing apart stringers, frames and any other load bearing parts in the process.

[@GregsAirplanesandAutomobiles]

Thanks Duke, great post.

[@ChristianMcAngus]

The Germans used mine shells, with a very thin jacket and maximum explosive load. which minimizes fragmentation effects to maximize shockwave effect. This is the most effective anti-aircraft cannon round when the round uses an impact fuse, like in aircraft guns. Surprisingly no other nation used this idea. The MK108 used the API delayed blowback mechanism where you had to choose between either a high rate of fire or a high muzzle velocity. The Germans went with the higher rate of fire.

[@dukecraig2402]

@@ChristianMcAngus No, it's not surprising and it's not necessarily the most effective, as I said those rounds work on the principle of overpressurizing the inside of the area they hit blowing apart stringers, ribs and other parts comprising that areas structural integrity but there's a trade off wherein it's far less damaging to any hard machinery it doesn't directly hit, something that throws shrapnel all over the place is far more likely to damage things in an engine compartment, wiring harnesses, external pumps on the engine, a generator and all the fuel, oil and hydraulic lines are more prone to suffer damage from a shrapnel type round, one little hole in an oil, coolant, fuel or hydraulic line and an aircraft's chances of making it back to it's base is greatly diminished. It's just two different ways of doing things and just like anything else from WW2 just because the Germans did something a certain way doesn't mean it's the best, especially when you consider that the Mine rounds weren't really that effective until they get up to the 30mm size, the German pilots complained plenty that the 20mm rounds weren't that effective and that it took too many hits to down or seriously cripple a bomber, 20mm has low enough rounds on hand and short enough firing time, up it to 30mm not only does that get worse but then you start running into size issues and the gun and ammo won't fit in the wing so they have to be put in a pod which increases drag, slows the aircraft, shortens it's range, decreases maneuverability and so on and so forth.

[@driftertank]

People going on about "survivor bias" were probably just having a pavlovian association between "report about guns shooting airplanes" and "survivor bias" because it's a meme...

[@edwardscott3262]

Anyone who thinks you can't fire a machine gun for 20 seconds has never been to a machine gun shoot. This was WW2. They knew bombers, planes, ships, and men were all expendable. A machine gun barrel getting worn out a little too quickly wasn't at all something they cared about.

[@GregsAirplanesandAutomobiles]

That's exactly right, in combat your concerned about living through the next few minuets, not preserving your equipment for the next war.

[@user-xj6rr3yv8q]

Bud Anderson talks about how firing 20 seconds with an air-cooled light barrel M2 burned out the barrel. He had a wingman do this, he could see the bullets spiraling in the air

[@davewolfy2906]

@@user-xj6rr3yv8q but, how worn was that barrel before that engagement? Perhaps that pilot had a habit of it. Also, he.might have previously been doing ground strafing, longer firing times?

[@alganhar1]

@@davewolfy2906 WWII fighter gun barrels were lighter than say the infantry .50 cals, or the navy 20mm AA guns. Yes, air cooling from the aircrafts movement mitigated some of that, but they did heat up more rapidly, and more importantly they wore out much faster. Don't forget, weight in aircraft is PRECIOUS. The more weight you can save the better. So yes, .50 cals and 20mm cannons developed for aircraft were significantly lighter than Land or Naval based versions, which meant they could suffer cooling issues. This is something that NEEDS to be understood. The guns in an aircraft may be the same calibre as an infantry heavy machinegun, or a navy light anti aircraft gun, but they were built a LOT lighter.... They were not the same. As ground troops found when they pulled .50 cals off damaged aircraft to use for the infantry during the pacific campaigns. The former Air guns had major issues with cooling. Still much better having them than not, but they did have serious issues when used in ground combat roles. Like they overheated, a lot.....

[@edwardscott3262]

@@user-xj6rr3yv8q I think I'm going to look into that more. I do know during the war they switched to lined barrels for the machine guns. I believe it was inconel but I forget exactly what material. They did it first for .50cals and then did the same for 1919s. They never fully adopted it for 1919s and it was luck of the draw which type of barrel you got even after the war. I do know tracers can do some really weird stuff. The tracer element is much lighter than a bullet and often still today can be dislodged and go places the bullet doesn't. Especially when something makes the bullet spin end over end, the tracer element can go flying off in a direction that the bullet didn't actually go. I'd imagine if in this testing they found the .50 cals doing that they'd have mentioned it. Especially since they were testing on the ground and would have found barrels heating up much faster than in the air. They certainly would have noticed if the bullets were unstable before hitting the target. A tumbling bullet is very obvious when examining the target. Going back to the tracer the tracing compound is much lighter than lead and steel so that tracer bullets tend to be much longer than their regular counterparts. The M-16A2 has a 1 in 7 inch twist because it was needed it to stabilize the longer 62 grain tracers not because it was needed to stabilize the SS109 bullet. So in any gun tracer bullets are more likely to destabilize than the other more normal bullets. It's just a necessary fault to deal with when it comes to tracers. They have to be longer just because tracing compound is so much less dense. I do know during the war in bombers they eliminated the tracers in belts because people were following the tracers and not the sights. When they were removed they found it increased the effectiveness of gunners substantially. They did try training it out of gunners but still found it necessary to just remove the tracers completely. It being one of those things you can tell people until you are blue in the face but they'll never believe it and still trust the tracers instead.

[@m.r.donovan8743]

Greg, thanks once again for producing THE most comprehensive and complete study of all of the major World War Two fighters, some of the bombers, and a few of the Great War aircraft that has ever been accomplished for public consumption. You are to be commended for your efforts, and for teaching the equivalent of a bachelor's degree in reciprocating aircraft engine performance and design. Have you considered creating similar videos for attack aircraft? Dive bombers like the Dauntless and Val, torpedo bombers, and the Hawker Tempest would be very interesting for me personally. Did you know that the SBD could be flown from the back seat?

[@Royalmerc]

Man, this channel is a real gem. Thanks for walking us through this amazing, yet complicated study. I don't think anyone else would take the time to do the same. Personally I think the gun still has a roll to play in modern aviation combat. The capability of stealth will open up better opportunities for it imo.

[@stephencastello6553]

Greg you are absolutely correct. MK as used in MK 103 and MK 108. MK 108 stands for Maschinenkanonen Model einhundertacht. It was affectionately known as die grenatenwerfer or the grenade thrower. MG 42 stands for Mashinengewehr Model zweiundvierzig.

[@Talon3000]

"Der Granatwerfer", but yes. "Mark" in german is a past currency (Deutsche Mark). German engineering doesn't use the "mark" designations at all. We tend to just put more numbers or letters after a name. May be a "Rev" for "Revision" or "V" for "Version"

[@volkerkalhoefer3973]

@@Talon3000 it ain't Mark, it's Maschinen Kanone (M K)

[@jimwatts914]

Tremendous overview of aircraft guns and the debate over what is the best. Clear explanations of complex issues is Greg’s jam.

[@sethbromley7186]

<a href="#" class="seekto" data-time="3325">55:25</a> The old Korean War-era flight sim Mig Alley discussed and modeled this concept well for its time. The F-86 had six nose-mounted .50s which were great for snap deflection shots or when trying to lead a target in a turn fight. You could spray out a nice stream of lead and let the target fly into it. The Mig-15 had big cannons, which it needed for going after American B-29s, but were harder to score with in a dogfight with a Sabre. You needed to pull much more lead to get those cannon shells on target so the Mig pilot had a much harder job in a maneuvering fight. But on the other hand you only needed one hit!

[@Eric-kn4yn]

And b36s but that never came about

[@TheJustinJ]

Mig Alley, thats an old game! Haha. The same effect can now be experienced in War Thunder, Sim mode.

[@TheCrashyBoi]

Hello! Amazing video, but just wanted to do a correction The soviet cannons on the MiG-19 arent primitive and uneffective. Just because it doesnt use revolver or multi barrel guns doesn't mean its worse. In fact, the NR-30 performed extremely well, with a high firerate and powerful guns that challenged american counterparts

[@kenneth9874]

Just because you challenge doesn't mean you win.....

[@kopfauftischhau216]

Done some reading about this tooic recently and one aspect i never really thought about before is volume. The change from 151/20 to mk108 was doable without other massive changes to the airplane.

[@kendavis8046]

Dammit! I was going to comment with a pithy response, but you covered it! Good job once again, Greg.

[@JWZelch]

Woohoo! A new video from The Man!

[@UkrainianPaulie]

As a retired US Army grunt, Ma Deuce was my baby. Spoke to a German WW2 veteran (Western Front) on a Volksmarch in 1989. He told me they feared the Ma Deuce. He replicated the slower rate of firing. " pop, pop pop". Told him we still use it. 2023 still going strong.

[@GregsAirplanesandAutomobiles]

They sure got their money out of whoever designed that gun.

[@kirbyculp3449]

That would be the venerable John Moses Browning. He also invented the Colt GM 1911, the BAR, the 0.30 caliber MG, the Winchester M 97 Trench Gun, the Browning A5 shotgun, the Model 17 shotgun that became the Ithica M 37. And the Colt 1903 and Colt 1908 pistols, which were issued to General officers. And the Superposed O/U shotgun, which may have been used recreationally by the military but that is only my supposition. And he started the design of the FN High Power an excellent pistol used by Allies AND the Axis powers. And more besides.

[@edwardpate6128]

@@kirbyculp3449 John Moses Browning, The GOAT of gun design!

[@mikebrase5161]

​@@GregsAirplanesandAutomobilesGun Jesus designed the M-2.

[@Eric-kn4yn]

No argument it was a disgrace arming british 4 engine bombers with 303

[@petersmythe6462]

There is a distinct difference between becoming a glider within 5 minutes and becoming metal confetti within 5 seconds. One of those planes is still an active threat and could happily kill the shooter's or other aircraft on the way down, land successfully on a friendly road or field, and have their aircraft repaired within days. The other is instantly out of the fight and never coming back.

[@MaxPalmer-1]

Another nice job, Greg, with some outstanding detailed data from the Optimal Caliber Report. But, there are a few things to consider from Pierre Sprey's report on fighter effectiveness to possibly add and compare. For example, it was noted in this video that with one engine knocked out, the P-38 could usually get home. Apparently the combat data shows otherwise. Losing one engine has greater than 50% chance of losing the aircraft by fire or by enemy fighters downing the cripple. And, since having two engines is doubling the probability of an engine getting hit in the first place (simply double the target area), the odds are generally higher of being downed by gunfire to a P-38 than to a single engine fighter. As you point out, there are a lot of statistical variables to this subject. Next, Sprey does a nice job of documenting kills per trigger "squeeze" (defined by Sprey as 4 seconds worth on a single firing pass) for different guns in real combat: 1. WWII, six 50 cal M2's, 0.4 to 0.5 kills per trigger squeeze. Our guys were well trained in gunnery, and six fifties would tear up a light prop fighter. 2. Korea, F-86 vs MiG-15, six 50 cal M3's, 0.34 kills/trigger squeeze. Higher speed, and a target more rugged than a WWII fighter. 3. Korea, F-86 vs MiG-15, four 20mm M39's, 0.29 kills/trigger squeeze. Sprey explains this as the lower sectional density of the 20mm projectile slowing it rapidly with range having a more negative effect than the greater power of the 20mm round. 4. Vietnam, U.S. aircraft vs MiG-21 and MiG-17, 20mm M61 Gatling gun, 0.25 kills/trigger squeeze. No explanation given, but likely the less practiced gun fighters of that era shooting at faster targets. 5. 1967 6 Day War and 1973 Yom Kippur War, Israeli Mirage 30mm cannon vs MiG 21 and MiG-17, 0.4 to 0.5 kills/trigger squeeze. Very powerful (though slower) round plus highly practiced Israeli pilots. They really emphasized gun kills in both these wars, especially in 1967. The Israelis had little faith in missiles in the 60's, and in particular did not like the performance and range reducing weight of radar missiles with their low Pk even in the 1970's. To my knowledge they used no missiles in 1967 (achieving 60 gun kills against 10 losses). They made more use of steadily improving heat-seeking missiles in the 1973 Yom Kippur War. In this larger conflict Israel scored 171 of 261 total kills with heat-seeking missiles (65.5%), 5 kills with radar guided missiles (1.9%), and 85 kills with guns (32.6%). Not addressed by Sprey is the number of shooting opportunities statistically achieved with each gun system. The issue of shoot downs per mission is a conditional probability that is influenced by factors that reduce shooting opportunities. Heavier guns would logically reduce agility and range, and thus lead to statistically less chances to shoot and perhaps fewer kills. You'd have to get to the peak point of this trade-off to achieve true "optimum". Sprey recommends a new gun system, a lightweight agility supporting 50 cal Gatling gun with 4000 fps muzzle velocity and heavy depleted uranium projectiles that will preserve that velocity better over range (and better penetrate modern jets designed for ruggedness), like direct fire artillery fades only slowly over distance and thus shoots very flat. He does not discuss the likely barrel life problems such high velocity would probably impose. Given how cheap gun trigger squeezes are compared to missiles, perhaps he thought more common barrel replacements were a transparent cost. I had a few exchanges with Sprey over the years about light vs heavy fighters, but did not ask him about the future gun subject, and he is gone now. He was a brilliant military operations researcher who always backed his conclusions with data and analysis, and as an engineer who thought the same way, it seemed to me that he did not make many mistakes. I wrote the fighter weapons section of the main fighter aircraft article on Wikipedia about 4 years ago, and the other editors have left it almost entirely alone. It is not nearly as contentious a subject as saying that light fighters could build a much better air force per budget, which if it becomes well believed common knowledge could threaten the greater than 10 billion dollar per year heavy fighter cash flow (though reality is probably forcing that cash flow into lower cost drones in the near future). It gives some details on issues like weight of fire per second for the various guns, and reliability of missiles over time. So, there might be some data and references given there that are useful to you.

[@GregsAirplanesandAutomobiles]

That's quite a post.

[@TannerG151]

My favorite remains the MG 151 with mine shells. More explosive filler than a Hispano, but still maintains middle of the road muzzle velocity. As the war goes on and planes get faster I feel damage per hit starts to matter more, as it becomes harder and harder to maintain aim for a concentrated burst. Good Video as always Greg 👍

[@knutdergroe9757]

Good Job Greg, The WHY is very important in U.S. military reports. I have been teaching firearm safety, hunter safety, and basic close combat for over 40 years. As well as military vehicle owener doing my own repairs. Why makes a huge difference in the military.

[@sadwingsraging3044]

Cumulative damage + critical hit probability × repair time² + parts/material availability = crashed/parked aircraft³ Big DAKKA wins battles. Logistics wins WAAAGH! Another great video Greg!😁👍🏻

[@spookyghost3209]

PAINT ID RED SO IT FLY FASTA YA GIT!

[@sadwingsraging3044]

@@spookyghost3209 🤣🤣🤣👍🏻 Can you imagine the look on Greg's face as someone tries to explain Speed Freaks to him? Preferably an AI created Margaret Thatcher going full Iron Lady with the descriptions.🤣🤣🤣🤣🤣

[@spookyghost3209]

@@sadwingsraging3044 I'RON GOB THATCHER IZ A BOSS WHO KNOWS HOW TA REALLY R'ALLY DA BOYZ

[@sadwingsraging3044]

@@spookyghost3209 Avenging Ole 👁 is the greatest respect and honor one Chad can show for another Chad.🎖😌

[@jacobhill3302]

There was a Luftwaffe field expedient AA weapon. A triple 15mm cannon mount I believe called a drilling or dreiling or something like that. The cannons were discards from aircraft that upgraded to 20/151. I believe, read all this years ago...

[@mlmmt]

When 1 50 cal is not enough, just add more until you think its enough, then add 2 more!

[@huwzebediahthomas9193]

Recoil on some sends some aircraft backwards into a stall - great thinking, isn't it? 707 eight rifles were bad enough on Hurricanes and Spitties.

[@kenneth9874]

@@huwzebediahthomas9193 the 303's were a joke, that's one of the main reasons british bombers were relegated to night missions

[@External2737]

P-47 with 8 50-cal MGs did fine. F4F, F6F, Corsair, Mustang, and P-40 did fine.

[@BearfootBob]

​@@huwzebediahthomas9193which aircraft stalled as a result of firing .50 cals? Any record of this happening?

[@sparkling925]

@@huwzebediahthomas9193 my guy they put tank caliber sized cannons on partially underpowerd airplanes and did fine, i doubt an array of 50 cals can do that to even a slow moving bi plane

[@TheJacobshapiro]

The air-to-ground argument is the reason I’ve heard for USAF going to 25mm. The logic is that cannons are extremely rarely used in air to air combat (as you mentioned, the last air to air kill by a US plane with cannons was in Vietnam) but cannons continue to be used from time to time for air to ground purposes, so it makes more sense to optimize them for this instead. A bigger shell can fit more HE, meaning generally a better effect on soft and lightly-armored ground targets, and muzzle velocity and RPM for a given burst mass matter less, hence the F-35’s 25mm. Granted, the F-35 still has an air to air gunsight mode, even on the B and C models that carry the gun externally. I think they figured that they might as well if the gun is going to be on the plane anyway, but I’d be very surprised to ever see it used in air to air combat.

[@sugarnads]

If an F35 has to go to guns the shit has thoroughly hit the fan.

[@welshparamedic]

Perhaps the later Mk spitfires fitted with the "E" type wing, usually seen in Mk IX and later versions were on the right track. They had the option of a a pair of American .50 caliber Browning AN/M2 heavy machine guns in place of the inner pair of Hispanos, giving an armament of two Hispanos and two .50cal Brownings. This configuration was often used. The Universal wing also took into account the fact that the Hispano cannon had been converted to belt-feed, a move which allowed each cannon to carry double the ammunition load, or 120 rpg in ammunition trays instead of 60 rpg as in the original drum-fed cannon of the Mk Vb. This also eliminated the need for under- and over-wing blisters to accommodate the large-diameter ammunition drum, instead only requiring a small blister to cover the electrical "Chattellerault" feed mechanism.

[@jackd1582]

* edit...inner brownings

[@wbertie2604]

In theory 4 20mm could be carried, and after further wing redesign with the 19 onwards, they were. The V was the first with the 4 20mm option but the outer pair had heating issues. I can't remember what the logic for using the inner 50s in the E wing was. The UK looked at 50s as an interim for bomber guns in the late 1930s but couldn't get a licensed production arrangement soon enough and didn't want to depend on imports, so development was ended in 1939 until 1942 and 1943.

[@johngriffiths118]

@@wbertie2604COG issues ?

[@michaelbevan3285]

The Belt Feed Mechanism was fitted because of persistent jams of drum fed guns as they found that the springs of the drums would fail to feed under G as they got older and the conclusion was that the rounds needed more forceful feeding to the breech so the BFM was installed and worked very well. They had learned from the French experience with the 20mm Moteur-Cannon in the 406 and D520, which suffered the same fault. It was also why the Germans developed the MG 151 as the Oerlikon was less well suited to aircraft mounting and not suited to engine mounting. One issue that the British found later with the Hispano was a tendency for parts of the breech to crack as guns lasted longer in service and there were issues in Burma with such guns in Hurricanes failing in flight due to cracks.

[@richardnicklin654]

Can be summarised as “don’t throw anything smaller than a Browning .50 round, don’t shoot slower than a Hispano-Suiza 20mm cannon”.

[@ndenise3460]

The German shell size (calibre)may have been but the casings were significantly different. 90 mms long in the mk108 vs 184mms in length. This would be like trying to fire a 30-30 in a 300 magnum rifle

[@Slahinki]

The shells they fired (at least the HE/M) were identical, and as you pointed out the cartridge was significantly longer. But not only that, the 30x90RB of the MK 108 was straight walled, whereas the 30x184B of the MK 103 had a cartridge body diameter of 40mm so it was also significantly thicker.

[@tonedeaftachankagaming457]

I believe Greg is saying in the video that the shells themselves were identical, both being loaded in to whichever case for the cannon. (edited because found the part of the video I was looking for)

[@emmanuelgustin7851]

The thin-walled high-explosive "Minengeschoss" projectile was the same, indeed in an entirely different cartridge. This was the only projectile used for the MK108. For the MK103, with its much higher muzzle velocity, traditional HE and armour-piercing rounds were also available.

[@lahockeyboy]

hiya Greg! I thought that there really wasn't much more to be said on this topic... but, of course there is in Greg's hands! Thanks, Capt !

[@PeteSampson-qu7qb]

Some points and conclusions: 1. I don't recall any AAF pilots saying "I wish I had a cannon". A few Navy pilots did. 2. As I understand it, the .50cal incendiary rounds were very good and self-sealing tanks weren't a whole lot of help against them. 3. My uncle was an ordinanceman in the AAF and, while I don't know if he had anything to do with these tests, he did have two pieces of a B-25 main spar that he said was sheered clean through by a single hit from a .50. Conclusions: 1.There isn't a single answer to the question of what is "best". Even within the context of WW2. 2. For the USAAF I think the .50 was the best choice. Weight, ammo load, and effectiveness against fighters made up for any lack of one-shot kill ability. 3.The Navy needed more stopping power as Japanese pilots became more fanatical. It's too bad we didn't get our 20mm right sooner. It would have saved lives. 4. I'm a bit of a gun nut and, when all is said and done, it's HARDER to hit a small target with a slow round. I have a .58cal muzzle loader and, while I can, after a lot of practice, hit a bedsheet every round at 500 yards, it won't hit a quarter at 10. I would not want a MK 108 if I was up against fighters unless I had at least two .50cals but four or six or eight would be better. 5. The MG 131 wasn't mentioned here but it really wasn't a match for the .50cal. Low muzzle velocity again. 6. If the RAF had switched to .50, either BMG or Vickers, when they adopted the Browning in .303? The Battle of Britain would have been shorter and a whole lot bloodier for the Luftwaffe. Cheers!

[@petersmythe6462]

The problem with the MK 108s isn't mechanical accuracy. It's gun lead against a maneuvering target. The difference of a plane pulling a 7 G maneuver for 0.5 seconds vs 1.0 seconds is substantial. One will be displaced 18 meters while the other will be displaced 72 meters.

[@Warmaker01]

Great video and nice conclusion. Air-to-Air against fighters was what the American air services were dealing with mostly in WWII, so those 6-8 .50 cals worked wonders. But the Axis air forces had to worry about multi-engine bomber intercepts. But those post-war developments look real interesting as the years went on.

[@williamromine5715]

Being an American born in 1942, my first love is the .50 cal. I really appreciated this video. I can still hold my head up for loving the half inch machine gun. Thanks.

[@xiphosura413]

A shame the MG151/20 wasn't included, there was a lot done with it post war but I suppose procurement after just a single year was tricky. Man I did not expect to come away from this with the MK108's "spud gun" reputation so rebuffed. Also interesting to note the difference in frontal vs rear attack, and the relative performance of the 37mm. Really puts in perspective why the P-63 was often given that extra pair of gunpods, two .50s just doesn't cut the mustard and it's difficult to rely on being consistent with the 37mm when .50s scale so well in numbers. Would love to see more cobras on this channel, real funky aircraft in many ways and some of my favourites. Also never really considered how the jet age really allowed fighters to have their cake and eat it too so to speak, for a brief period at least centred around the F-100 and Hunter.

[@dev1360]

Currently listening to "Masters of the Air". He says in chapter 1: "the P47s didn't have the range to escort the bombers in 1943." I'm like "NUH UH!"

[@WALTERBROADDUS]

P47 did have a range problem.

[@sparkling925]

didnt the us refuse to use drop tanks on p47s at first? dont know if it was a problem in 1943 tho

[@WALTERBROADDUS]

@@sparkling925 yes, in 1943 the P-47 could not reach Berlin.

[@gort8203]

@@sparkling925 They didn't "refuse", they just weren't available yet in early 1943..

[@dev1360]

@@gort8203 not true

[@robertkb64]

Just starting to watch: in Naval terms we’d typically talk about minimum penetration (in inches of STS or inches of Class B armor) and throw weight (in lbs per minute), so I’m hoping you include something like this. So .30 might be almost useless because it doesn’t have the penetration needed, while the 37mm has plenty of armor defeating capability but probably fires too slowly. Comparison point though: even in WW2 the US was using radar for Naval gun fire, which could be meaningfully adjusted for a miss between shots except at extreme ranges, and I don’t think there’s an analog for that in aircraft even today, suggesting that higher total firing speed may be more important to an aircraft than it is for a 16 inch naval gun. Compare USN Iowa Class with IJN Yamato - the Yamato throw weight per shot was much higher, but with a fire rate so much slower than every Iowa had a higher throw weight over any time beyond the first salvo (though keep in mind that a salvo from an Iowa is 9 x 2600lbs of APHE).

[@lamwen03]

Aircraft armor was typically used only to protect the airmen. The mechanical systems themselves had to take their chances, so really it was a balance between probablility of hits vs. damage per hit. Like the battleship guns.

[@Mishn0]

@@lamwen03 That holds up until about 1950. Once jets were the pointy end of the stick the .50 wasn't big enough. Jets had thicker skin to withstand the greater stresses involved in high speed flight. That's what got the Air Force to switch to cannon for their fighters' guns. They found the .50s of the Sabers were failing to penetrate MiGs' skin at the ranges they were fighting at, at least in a tail chase when the angle of impact tended to be shallow. That mattered when deflection shots were getting harder to get hits with with the increased speeds of combat. Just hitting wasn't good enough any more, you had to hit hard enough to penetrate.

[@nightshade4873]

@@Mishn0 the more reasonable answer (and adding to @cancermcaids7688) is simply due to increasing speeds in which dog fights are being fought at, which reduced the "on-target" times that pilots doing dogfights would have faced, a rotary cannon could spit out more than a .50 M2/M3 (variants of the Browning M2 modified for multiple purposes), not only that, the 20mm Munitions utilized in the rotary cannons would have better ballistics due to having more mass (see F-111 Incident), and would take less internal volume than multiple .50 M2/M3 machine guns, or if not less could take equal internal volume for more ammunition stored though this is varied on multiple designs Also, remember that Aircrafts only have armor to protect critical components, most especially the Pilot, they don't have all around armor like that of Ground AFVs, rounds don't bounce around like you would see from Top Gun Maverick (or if not the earlier rendition)

[@paqx3534]

Aircraft started using radar corrected gunsights in the Korean era. F86 used them to great effect against MiGs, which at the time were still on manually corrected gyro reflectors. The history of A2A corrected gunsights starts far earlier than one might expect.

[@robertkb64]

@@paqx3534 Do you know how those radar corrected gun sights worked? Battleships (at least Iowa + Montana, though she was never built) used radar on the turret to calculate actual projectile velocity and compared this against expected values to know if each gun was shooting faster or slower than expected and then watched for fall of shot, so it could compare actual performance with expected performance and adjust each shot angle to account for real-world condition (on top of the typical fire control system, which calculates based on temperature, humidity, coriolis effect, firing vessel and target range, speed, and heading, ship roll, age and expected wear of each barrel, and a few more that don’t come to mind), all done with mechanical computers (that’s the Mark 38 Fire Control System for those keeping track….. and it’s still the best Naval gun system). Anything like that in aircraft? The only modern aircraft I can think of that fire their guns often enough to really benefit are the A-10 and Su-25m (and the AC-130, of course).

[@BruceGCharlton]

Very interesting video. I think there is a decent case for saying that the fifty caliber machine gun was the best weapon for dogfighting between (single engine) fighters, with fighters being easier to damage and shoot down; while the 20mm cannon was superior for attacking larger and multi-engined aircraft such as bombers, and for most fighter-bomber attack missions (against ships, trains etc). The USAAF fighters were mainly designed and used against other fighters, which makes fifty-cal the best option. In other words, fifty-cal best for escort fighters (i.e. fighting other fighters), 20mm cannon for interceptors and ground attack. One question I haven't seen addressed is whether there was much advantage from a mixed armament of machine guns and cannon. There are several definite disadvantages - in terms that the convergence will be poor due to inevitable differences between machine guns and cannon in muzzle velocity, range etc. But I presume there must be advantages too - because many aircraft had both machine guns and cannon throughout the war - e.g. the ME-109. My best guess is that the cannon armament was primary, but more prone to malfunction, and machine guns were a back-up. Therefore the mixture was a compromise. When cannon became reliable, then most aircraft moved to cannon only - e.g. the Spitfire, which was primarily an interceptor, went over to 4 X 20mm cannon when these became sufficiently reliable.

[@charlesmitz5239]

50 cal was an excellent gun. Not as good as 20 mm canon but close enough as not to matter unless you're focused solely on destroying bombers

[@huwzebediahthomas9193]

50 cal, one burst, and you stall. Horrendous recoil

[@guaporeturns9472]

@@huwzebediahthomas9193huh?

[@MatigrisSH]

@@huwzebediahthomas9193 thats.... just not true at all....

[@2552legoboy]

@@huwzebediahthomas9193very action has an equal and opposite reaction. 50cals weigh less, have less gunpowder than 20mil simple maths

[@sparkling925]

@@huwzebediahthomas9193 you can fire 50 cal out of a rifle, its not gonna make an aircraft stall

[@Jewclaw]

I get excited for your videos Greg, like from back in the day when your favorite show came on Friday night at 7pm

[@davidpf043]

20mm on the F-8 Crusader was famous for one thing, jamming. Probably failed about 75% of the time when used in Vietnam. Famous as "the last of the gunfighters" the F-8 scored three gun kills with the rest AIM-9D.

[@nickmitsialis]

But did those F8 kills work because the AIM9 was such a darned good missile or because the 'Last of the Gunfighters' knew how to get into good firing position before hosing their opponent? I 'feel' that actually knowing how to 'dogfight' was a gun armed jet was a great advantage over a flying flatiron like the 'Thud' or the Phantom.

[@conroypawgmail]

I don't know how many of them were actual jams, with the round or belt link stuck in the gun. I think most of the problems that brought the gun down was broken ammo links.

[@Sturminfantrist]

@@baronvonslambert Like the RF- Reconnaisance Models the G Model didnt need a Gun for its Role it was a "Wild Weasel" built/tailored for the SEAD role .

[@filthydisgustingape5354]

@@cancermcaids7688 yes, those Vulcan cannons came in handy. The lore has it, the gunsights were usually set in air ro ground; the pilots would just fire and guide by tracers. The fun thing was, this and the Six Day War proved the worth of an internal gun in modern fighter jets.

[@gort8203]

@@nickmitsialis The F-105 shot down more MiGs than the F-8, and all but one of them was with the gun.

[@raulduke6105]

My old man was a usaf 35 yr man knew lots of pilots who stated it was so hard just to get a hit they wanted the biggest round their aircraft could carry

[@peceed]

Big bullet solves the problem of underkill.

[@Jwalker21NC]

In regards to if the M2 could sustain 20 seconds I’ve heard on more than one occasion in the prob 100-150 different first hand accounts of P-47 pilots telling their stories (mostly on American Veterans Chronicles) that they could fire all the onboard ammunition even at a full load in one burst. I don’t have the references on hand but will look for them and post them. Their accounts state that they could sustain fire for that long if necessary but usually did not as you said for accuracy purposes. Another great video Greg!!

[@neoconshooter]

I can't seem to help myself! The Germans actually built two Me-262s with two Mk-103 cannons instead of four Mk-108s because of the problems encountered with getting hits with the Mk-108! They were actually going to switch weapons fit because of it. They also built a special Mk-103M for installation in Me-109s. My landlord claimed to have flown this plane in combat and actually shot down several 4E Bombers and a P-51 with it! All from outside the effective range of the bomber's defensive guns. Quote "One or two hits in the cockpit and they all go down!" This with the Very high velocity Ausf-"C" Minengeschloss shell. This version of the mine shell was much more pointed and held less explosive than the standard Mine shell. His standard technique with the Mk-108 was to open fire from 700 Meters in front, down the throat to 400 Meters and breakaway down and to the fast roll side to make as violent a maneuver as possible, so as to avoid the bomber's guns. (Using the engine-prop torque to aid the rate of roll.) I sincerely hope that all this trivia helps!

[@kenneth9874]

50 cals are effective beyond 700 meters

[@michaelbevan3285]

what was the name of this landlord of yours?

[@kimmoj2570]

<a href="#" class="seekto" data-time="2560">42:40</a> M-shells were not built like other cannon ammo (forged and machined). They were built like rifle bullets, drawn from sheet of materiel, and had massively larger HE content. MK-108 shell had 85g of explosives. Thats equal to blast of hand grenade exploding inside of aircraft. Tests done by Brits proved that one 30mm hit could severe whole Spitfire after fuselage from rest of aircraft.

[@hillarysemails1615]

<a href="#" class="seekto" data-time="3300">55:00</a> You are correct. 30mm was for use against bombers and the thin armor of tank engine decking and the 15mm at the top of tank turrets. 37mm was even better against tanks, as the AP tips could shove its way through the armored decking and then explode the few grams of explosive once inside the crew compartment or engine area.

[@mitchelloates9406]

On the Vulcan cannon - from what I've read, the idea of basically combining a multi-barrel Gatling gun with an electric motor, to produce a machine gun or cannon with an extremely high rate of fire, dates back to at least the 1890's - a couple sources saying that even Dr Gatling himself experimented with the idea. The main problems quoted with trying to develop this system, was designing an ammunition feed system that could reliably keep up with high rates of fire, as well as an ignition system for the ammo itself, again that could reliably keep up with high firing rates. Apparently, the reasons that there wasn't much of an effort put into developing such a weapon until the late 40's/early 50's, was that this was a bulky and complex system with high power requirements, compared to the "standard" machine guns and cannons of the day. And up until that time, most militaries didn't see the need for such extreme rates of fire, as in the pre-WWII era the conventional machine guns and cannons had proven adequate for their needs.

[@GregsAirplanesandAutomobiles]

A big problem with this in an aircraft was rotating the barrel. See my video on the B-32 Dominator to understand the limitations of aircraft electrical systems. Once the jets came along, this wasn't a limitation anymore because those engines could turn much more powerful generators.

[@petesheppard1709]

Thanks for mentioning the US Navy and their transition to cannon after WWII; I believe the change was actually begun right at the end of the war, influenced by a perceived need to score quick kills on kamikazes. A video on their reasoning and research would be greatly appreciated. As a bit of an aside on damage to V-1710's cooling system, I once saw a statement that P-40s were less vulnerable to cooling system damage since the radiator was packed up under the front of the engine, rather than spread out in the wings and fuselage. LASTLY, and totally random: I have a really hard time wrapping my head around the fact that, right after the war, all those aircraft and parts were pretty much regarded as junk to be disposed of whatever manner deemed appropriate.

[@WALTERBROADDUS]

I don't understand why you don't understand why these aircrafts were disposed of? They were obsolete. Many of them damaged. With military downsizing they were Surplus to requirements. And had little civilian value. Nor were most people in the world thinking anything besides demilitarization and rebuilding.

[@trauko1388]

The USN was trying to replace the obsolete M2 from early on in the war, but the US screwed up Hispano production and was forced to keep using the M2.

[@petesheppard1709]

@@WALTERBROADDUS Yes, I do understand all that. Like I said, they were regarded as junk. From a 2023 context, when these birds (and parts) are rare, valuable and cherished it still hurts a bit.

[@jfess1911]

@@trauko1388 I had read on Anthony William's website that a minor dimension error is what caused the US version to be less reliable. His recently published book "Autocannon" probably covers it as well.

[@trauko1388]

@@jfess1911 Ive read the same... how the hell do you screw up dimensions whne you are handed the damn blueprints??? I think it was rather stubbornness than a mistake,

[@normkeller2405]

Those rear to front firing passes on Mossie Fighter Bombers might be more exciting than apparent in the videos.

[@petersmythe6462]

"They are of no consequence in WWII" I mean, to be fair, a 100mm shell would do some serious damage to aircraft and with a beehive round or proximity fuse could absolutely demolish enemy planes. Basically a flying AAA.

[@matthewf1979]

I could have sworn that the Hi-Standard/Frigidaire improvements to the M2 were in service by summer of 1944. Not that rate of fire matters when you’re counting damage per hit. Maybe I’m mis-remembering or misunderstanding when the M3 was on aircraft. I could have sworn they were flying over Germany for almost a year. Anyways, they’re one hell of a ripper of a machine gun. Great video Greg!

[@wbertie2604]

Got to love a 20mm that shoots down 109s and keeps your ice cream cold too

[@kadevohn]

youve gone and done a damn good job with this one brother. the boys are proud of you

[@fnorgen]

-For the purposes of this report they counted the other crewmembers as "structure". I understand why they did it, but something about it feels particularly brutal.

[@GregsAirplanesandAutomobiles]

It really does make one uncomfortable with what seems like a disregard for humanity.

[@crazypetec-130fe7]

Yeah, as an old C-130 flight engineer, that made me wince.

[@thisnicklldo]

I get the idea that it seems cold, but what choice did the the analysts have? Add another column/row to every (already complex) table for 'other crew injured', which would add nothing to the analysis. Leave off such hits entirely? But then, they are hits, and should be counted. I quite understand the analysts thinking 'we'll just have to add them into one of the other categories'.

[@neoconshooter]

~<a href="#" class="seekto" data-time="3180">53:00</a> INC stands for Incendiary. In 20 MM ammo, this is a shell WO explosive but filled with a detonator-fuse and Thermite, or Barium Nitrate, or Aluminum/Ammonium-Nitrate as an oxidizer. It's thick-walled steel body allows it to perforate many "soft" parts of the plane while burning along the way, hoping to start a fire. Fire was widely believed to be the number one cause of loss of the plane. HEI stands for High Explosive-Incendiary and contains powdered aluminum to stretch the time impulse of the blast and give a shell that hits a fuel tank a good chance to start a fire. Virtually non-existent WO the powdered Aluminum. Ever think about how they put out oil well fires with explosives? In .50 caliber projectiles the AP is a hardened steel core with the "I" being a Magnesium, or white phosphorus charge in the tip of the shell. This is torn open by the target's skin and ignites on contact with the air, showing a hit and possibly starting a fire in a fuel tank below the skin.

[@xardozz]

Great video, Greg. One thing I saw on a report some time ago that used this data, but in conjunction with plane type and target type per plane. On most fighters (and even some bombers) the TYPE of shooting was instrumental on armament decisions. Static and deflection shooting were the primary categories. Until the late 1950s it was difficult to have a 25mm that could keep up with an M2 for rounds on target - cyclic rate. (Think of throwing more SH#t on the wall) not to mention weight of the weapon and ammo... and here is the clincher - reliability. The .50 was normally the winner when it came to deflection shooting until the '50s. Advancements in the 20mm and 25mm guns have changed much. Not to mention Advancements in the ammo itself- i.e.don't shoot a modern 20mm in a 20mm weapon from ww2. Modern ammo is faster, has lower BAC and better cross-sectional density.

[@spookyghost3209]

Just a heads up, the mk103 and 108 shoot the same 30mm warhead but you cannot shoot a mk103 cartridge out of a mk108 because the 103 cartridge is actually over twice the length of the 108's. Although the comment on powder amount may allude to you already knowing.

[@johnlovett8341]

Awesome as always. Thanks Greg! I've long been interested in the U.S. 60 cal experiments. Also, in some experiments a 50 cal bullet was in a necked down 60 cal or 20mm cartridge for a blisteringly fast round. Still, a good weapon in large quantities in a timely manner beats a few perfect weapons 3 years too late.

[@Knuck_Knucks]

Greg's Airplanes. Coming in hot ! 🔥🔥🔥

[@lamwen03]

Nice differentiation between target types, bomber vs. fighter.

[@cannonfodder4376]

Got done watching this through. Splendidly informative and comprehensive.

[@washingtonradio]

The context of the study was important and when it was done needs to be remembered. It showed what characteristics would make an excellent aircraft gun.

[@petersmythe6462]

I find it kind of shocking that the P-47 could take a hit from an MK 108 and not only fail to be immediately blown to smithereens, but have a whopping 57% chance that it will keep flying basically until it's out of fuel.

[@GregsAirplanesandAutomobiles]

It is quite shocking. I wish they would factor that into DCS.

[@TheJustinJ]

I like every one of Gregs videos before they start. Never been disappointed.

[@GregsAirplanesandAutomobiles]

Thanks, I appreciate you kind words.

[@diggLincoln]

When are we going to get a video on ww2 submarines? We takked about it awhile back…. This world needs you’re genius on the subject! Thanks man

[@GregsAirplanesandAutomobiles]

My local WW2 Submarine near Tulsa Oklahoma was closed down for a while so I couldn't get to it. We had really heavy rain and it raised up and floated away. It's back now, secured in it's new moorings. She sunk several Japanese subs, so she is a real piece of history. I'll get to a video about her at some point.

[@samadams2203]

All I can think of upon seeing technical intelligence's logo is a Sphinx are the Venture Brothers. Nice video.

[@brudenell27]

I have crash relics from various ww2 planes and having .303 rounds and .50 it amazes how the tiny .303 rounds the British planes used did manage to take anything down

[@wbertie2604]

The UK wanted 20mm cannon as the standard for fighters (1937) and bomber defensive armament (1939). But war were declared

[@ChrisHodgsonCorben-Dallas]

The 303 incendiary rounds were very good and under appreciated part of Battle of Britain. You can see them glowing and igniting in the gun camera footage of the time.

[@kenneth9874]

​@@ChrisHodgsonCorben-DallasLol

[@richardrichard5409]

Little commented on. When the Spitfire was designed it was always forseen that cannon armament would be used but, they couldn't get the Hispanos to operate reliably, as regards accuracy, many pilots complaining. Purdeys, of shotgun fame, we're instrumental in resolving this. The barrels were bent, from poor metallurgy selection on pattern produced versions. In their boardroom is a letter from the King thanking them for their help, with a Purdey being knighted...although the problem was resolved by the head barrel maker. Source. Edward James Comben, my father and ex Purdey barrel maker😎

[@BlueBaron3339]

On the math page there's a reference to von Neumann, which must be Johnny von Neumann. Many claim he was the smartest man who ever lived. Well...the only people making that claim were the smartest people of the time, and all of them smarter than me 😂 Yes, he's best known for his work on The Manhattan Project. But he also worked on ballistic studies such as the ones you cite. He also created a computer climate model in the early '50s that predicted global warming. So I get it that he made brilliant people feel dumb 😉 Pardon my digression. Great video Greg!

[@GregsAirplanesandAutomobiles]

Thanks, all that math is far beyond my ability.

[@BlueBaron3339]

@@GregsAirplanesandAutomobiles Oh, lightyears beyond me too! 😆

[@SeannoG1]

I come home work, and Greg has dropped a video for me to relax to. Good night already.

[@bo12328]

Comments for the algorithm. Likes for the like Throne!

[@iflycentral]

Banter for the banter god!

[@johngilbert6036]

In Vietnam our 50 cal barrels would glow red, so were changed out regularly and fired a lot longer than 20 seconds. A gun would have 2 barrels at most usually 1. The average 100+ ambient Temp not -30 as at altitude. Your facts are interesting as always, THANKs!

[@live1poem]

As usual, I am impressed with the thoroughness of your research and how you respond to viewer comments and how you anticipate viewer perceptions and expectations. With this piece, I am curiously struck by the clarity of your monolog. This is a pet peeve of mine. In your style, it might be supported further, saying 'criticism '. I really don't regard my time spent listening to this type of programming as 'entertainment '. As such, concise expression is typically dispensed with in preference to nifty turns of phrase, corny sound effects, or digressions and homilies (even worse, bad electric guitar) No, I wish to be informed ! For this purpose, complex arguments are pursued most convincingly by pertinent data organized in logical sequence. In short, let me congratulate you for a clean presentation of a subject you admit is, even today, still an open question due to the number of variables. Lastly, please accept my compliment as a viewer of more than a dozen of your productions. You manage this without being too dry.

[@ugarit5404]

Great vid,confirms that fighter models in warthunder are realistic. Bombers are too fragile tough. Best caliber depends if you optimize more for ground strafing or dogfighting,but its always in the 20-30 mm range

[@mrcat5508]

Also depends on br

[@USAACbrat]

The 20 mm had a troubled introduction to the RAF with multiple failure to feed and failure to eject with their 20 mm.

[@kimmoj2570]

Early Hispano twisted like trying to push living snake to gun barrel. It was designed to be bolted to V-12 engine block, and Merlin was not designed for that, instead Hispano was wing mounted, or in nose/fuselage of twin like Whirlwind/Mosquito/Beaufighter. It took couple years to make it work. But Hispano was essential jump on firepower.

[@garylewis3641]

The m2 50 cal really helped win the war in my opinion!

[@brucebaxter6923]

Everything helped win the war. Except for USA businesses supporting Germany.

[@witchkinglp]

interesting fact: almost all successful 20 mm guns trace their origins (or at least their ammo) to Switzerland in one form or another. Rheinmetall developed its 20 mm AA guns in Solothurn - the due to Versailles treaty restrictions, Hispano Suiza's chief engineer and co-founder Mark Birkigt was Swiss, as were the Oerlikon guns of course, and an often forgotten one is W+F Bern's FMK 35 (FMK stands for 'Flugmotorkanone' = aero-engine-cannon in English) designed by Adolf Furrer (if you're a gun guy, you'll know exactly how it operates), which used a 20 x 139 mm shell, which is basically the same shell used by a number of 20 mm AA guns to this day. It was used in post war Oerlikon designs which is why it's so widespread today. The only major exceptions I can think of would be Mauser's 20 mm guns (and their derivatives, including guns used by the US to this day) and the soviet 20 mm guns. Basically all sides of the war used developments of Swiss 20 mm guns. I think it's rather interesting for a small netural nation to have had such a noticable impact on weapons design.

[@TheJustinJ]

<a href="#" class="seekto" data-time="61">1:01</a>:15 the 27mm Mauser revolver cannon has a unique performance metric, and that is it has the most total rounds and projectile mass fired in the first fraction of a second vs rotary gatling gun style cannons, which take approximately a full second to spin up to full rate of fire. In a modern jet engagement, almost all gunfire is short bursts of a second or less. Where the 27mm is firing about 2-4x times the firepower of the 20mm gatling guns due to its full rate of fire commencing upon the first round leaving the barrel. There was a study done in the 70s that determined two of these 27mm revolver cannons to be the end-all of arial dogfight armament.

[@GregsAirplanesandAutomobiles]

Those Germans were clever.

[@k9killer221]

One of my key refences is Gunther Boemert's book "Heaven Next Stop" where he is clearly flying a FW 190D. He said only 6 shots from his cannon separated the whole rear fuselage of a B-17 and he could see the pilots/cockpit from dead astern. Horrible, but quite informative.

[@GregsAirplanesandAutomobiles]

I haven't read it, but "six shots" could mean quite few different things. He can't mean 6 rounds, the trigger in that plane fires both cannons at the same time and only in a fully automatic mode. Maybe he meant 6 hits from his cannon shells. Yes, six in the right spot could destroy the plane, especially if it was already damaged.

[@k9killer221]

@@GregsAirplanesandAutomobiles That's right. He estimated six hits and he was very close to the target also. Just out of interest, does the B-17 have a structural weak spot around the waist gunner fuselage area, (which is where it broke off) or was it just because that's were the damage was concentrated?

[@ryridesmotox]

Comment for the algorithm... An hour+ presentation about ww2 machine guns and cannons mounted in aircraft. HELL YES!

[@BV-fr8bf]

75mm on the B-25. How many hits to sink a Japanese destroyer?

[@PupthePitbull]

Probably way more than they could land on one. Would probably run out of fuel before they even put a dent in one.

[@goldleader6074]

They probably only used high explosive rounds in those B-25-mounted 75mms, they would probably need some armor piercing ammo to sink a destroyer.

[@grathian]

Remember, the 3" gun is still a peashooter to a destroyer, and doesn't fire fast enough to score many hits on a pass. It is far deadlier to a merchant. On the otherhand, the B-25s 8-12 .50s will not do much individually, but together are a buzz saw, and Japanese DDs, unlike Fletchers and later USN DDs, are not armored.

[@goldleader6074]

@@grathian B-25 with a 75mm probably would do some damage if the AP rounds came in from above and hit the thinner lightly armored/wooden decks, even HE 75mm would do at least some damage to personnel, guns, and equipment but maybe not enough to cause sinking.

[@wbertie2604]

It was intended for use against transports, not destroyers.

[@68orangecrate26]

Dad flew Sikorsky H-34s in Vietnam. THE redeeming quality of that helicopter was the protection from small arms fire afforded the flight crew by the radial engine that was mounted in the lower nose.

[@sylwiamilewska]

great video as always! but for the love of god please capture/render DCS at 24 or 30 fps

[@Carstuff111]

Man, ok I am clicking the bell. I keep missing this kind of stuff when its fresh. I mean, I am glad to watch it now, but I enjoy this kind of stuff to help me keep my sanity these days lol. Great videos, truly!

[@whoprofits2661]

As an aside, I would also mention Yak-9K's monster 45mm cannon.

[@hahaayukko5543]

I think the lack of heavy bombers on the Axis side also played a part in not really needing 20mm cannons when 4-6x 50 cals. would rip a Ju 88, HE 111 or Do 17 to pieces easily.

[@jporter504]

Excellent video.

[@michaeltabeling2168]

Again great technical vid. Thank you a million.

[@vvvci]

45 bombing missions painted on the P-38 with 3 Nazi crosses (German planes shot down) in the picture... and the P-38s were used extensively AS BOMBERS as well as fighters (air cover) all through the Pacific from New Guinea in '42 to the bloody U.S. invasion of the Philippines Oct 1944 Although the P-51 Mustang gets more glory as a long-range fighter, and the P-47 as a ground attack fighter bomber, the P-38s were real workhorses all the way up to 1945 According to Gen. Kenney's "Air War in the Pacific," one of his P-38 fighter squadron wing commanders on a fighter sweep over the PIs called out 3 different Japanese fighters, and with a brief long-range burst at each, shot all 3 down in flames before the other pilots in his flight even got started That's impressive shooting... and firepower (1 20 mm and 4 .50s in a very compact cone of fire)

[@m1t2a1]

I'm glad I paid attention back when you were describing weight of shot in the air.

[@SheriffsSimShack]

Video is like always just great

[@GregsAirplanesandAutomobiles]

Thanks Sheriff.

[@20chocsaday]

It is good that you are able to use data that was written down soon after it was created. Most servicemen and women I have spoken to couldn't say much about what they did come the early '60s. They are more likely to remember and tell with pleasure the stories what they did wrong. Although an exception was one who only admitted to some knowledge of Morse code. More likely are the occasional stories of wrongdoing, trading and being surprised at the speed of the only V2 he saw when he was looking for their sites to destroy. (I think it gave him a fright.)

[@neoconshooter]

Great research! By 34:xx Minutes, you had pointed out the difference between the three rounds of a single hit to the engine doing "A" or "B" level of damage, but you failed to adjust those numbers by the number of rounds fired in any given time period and the reduction of dispersion between .50 Cals and 20 MMs! The .50 has, depending on exactly what plane it is mounted in, about half the dispersion at any given range as the Hisso 20 MM GUN! Rate of fire changes those numbers significantly! More later as I finish watching the video. Great work digging all this old stuff up! I thought I was the only guy in the whole world who paid any attention to it all those years ago!

[@randyhavard6084]

Glad I get to finish my day watching this video