Yanks and their MG's
 

One thing I've found curious the deeper I've gone studying the fighter development from 1930's forwards is that why did the US stick with 50 cals as their weapon of choice on fighters for so long?

I'm no über-guru in the topic, but during WW2 for example the only cannon I find is the hispano in P-38. Then even going to the jet age P-80 and F-86 both had MG's until F-86 H model.

So was it the high rate of fire, smaller weight, logistics of the ammo, the lack of bombers to shoot down or didn't they just get the advantages of a bigger caliber until later?

You basically answered your own question. BTW, there are 20+threads that are 20+ pagers dealing with this topic here and the ubizoo.

Flyingbullseye

Essentially all of those reasons are while the .50cal stayed on as the primary weapon in the USAAF and USAF arsenal until and during most of Korea. The US Navy was starting to switch to 20mm cannons midway through World War II but the lack of a reliable 20mm prevented most of that switch until post war.

With the USAAF - Having the .50cal around meant that the ammo supply logistics were simple (same basic rounds could often be used in airplanes or mounted on jeeps or in emplacements on the ground, etc.). There was also quite a bit of debate around how effective, in the hands of an average pilot, a bank of rapid firing machine guns were versus cannons.

In-game some of that newbie advantage is negated by having a point dispersion like some aces preferred rather than a wider kill box that helped newbies.

.50 Cal rapid fire??

I like the 50 Cal,its very strong,probably the strongest non explosive shells.
They use that MG till today.

Well 800 rounds per minute (ish) is fairly fast yes? The M3 .50cal that they used in Korea was over 1000 rpm I believe. Not that many other weapons used during World War II have a vastly higher rate of fire.

If I had been a P-38 pilot in WWII, I would have asked to have the 20mm removed and replaced w/ 2 50 cal's.

simplest way to explain... its easier to hit something with a spray of bullets than it is to hit something with a few big bullets that hit pinpoint... in other words your aim doesn't need to be as good with a bunch of small guns over one or two big guns.

In-game i prefer bigger bullets with a lower rate of fire, because they do more damage, usually i only have to hit once or twice to take out anything and my accuracy is good enough that i'll hit most of the time.

You have no idea what you have just unleashed, have you. :grin::rolleyes:

The simple answer is that the USAAF and USN wanted the 20mm, but US built Hispano cannon were very unreliable. Consequently, they had to stick with .50cals. Given a general lack of bomber opposition, .50cals proved sufficient, and even up until the end of the war US Hispano cannon remained unreliable.

After WWII, the USAAF was quite happy with its .50cals, but the USN still wanted 20mm, and they finally had a reliable version of the Hispano.

Rate of fire between a M2 .50cal and a 20mm Hispano cannon are very close, and most estimates of the firepower of a Hispano cannon give around 3-3.5 times as much power for the same firing time as an M2 MG, so the 4 20mm of a Tempest or Spitfire Mk.21-24 have an equivalent firepower to between 12 and 14 .50cal MGs. Even an E Wing Spitfire with 2x20mm and 2x.50cal has firepower equivalent to 8-9 .50cal MGs.

Nope, I didn't know that this topic that has puzzled me for the past few days had already been locked into a pandoras box in the forums. :grin:

Wasn't the later Hispano's like Mk V. used in Tempest pretty realiable already? And what kind of failure rates are we talking about with Hispano? Did it jam every 10th belt or what and what made the RAF to go that direction instead of sticking with the MG. So why did it take until mid 50's or whatever to mount them?

And what about the cannons on Russia and Germany used? One would assume that the technology and production blueprints would have been either handed over through reversed lend/lease or captured as the US pushed deeper into germany. Were VYa-23's and ShVAK's just as unrealiable as Hispano's?

The British Hispano was reliable, the RAF had eliminated almost all the problems by the time production moved to the Mk.II, and the Mk.V was very reliable.

The US M1 version was a very different beast, with a high rate of misfires and jamming. The US tried to fix the problems with the M2, but it was equally unreliable. The RAF had been hoping to use US built Hispanos to supplement British produced models, but these proved too unreliable for service introduction.

The problems with US built Hispanos were not solved until after WWII, and in the meanwhile they were only used on aircraft that could mount them in the fuselage, which reduced the problems caused by vibrations and flexing wings, although the misfiring problems remained. Even there they were not very reliable (there is a good reason the P38 had a mixed battery of 4 .50cals and one 20mm).

There was also the 'problem' of using other nations more reliable ammo, and feeding one's own industry (you know, making me[an american at home] rich at the expense of our boys on the front).

;)

If I had a P38 id ditch all the 50cals and put in like 4 20mms and pack in as much ammo as possible...also make them so they fire alternate instead of all at once so I get better coverage of my rounds...in Il2 the cannons fire slow and the target plane flies between the volleys of cannon shells. The 50 cal is a nice weapon it has good punch and good RoF and all but hte 20mm is just better :cool:

4 centreline mounted 20mm cannon would pack one hell of a punch, and the Hispano Mk.V is only marginally heavier and bulkier than an M2, so replacing 4 M2s with 3 Hispanos would actually result in a weight reduction, though the heavier 20mm ammunition would mean a slight overall increase in loaded weight. The size of the P38's nose would also allow for a lot of ammo, maybe even 250-300 rpg. The Hispano Mk.V has an almost identical rate of fire to an M2, but the alternating fire would still be useful.

Imagine a P38 with this armament and the same Merlin engines as the P51 :cool:

The wikipedia entry on the Hispano autocanon touches on the problem. The American showed interest in the British Hispano early on, but it appears the US manufacturers wanted to redesign the chamber somewhat. The result was that the weapon became prone to misfire. The USAF and particularly the USN had planned to phase out the .50 by mid war, but the American Hispano was delayed. Not until introduction of electrical firing post-war, did the US version become reliable enough for use in planes.

If the Americans had solved the design problems (or not redesigned the Hispano in the first place), Mustangs and Thunderbolts would have flown with 20mm Hispano canons rather than MGs. Luckily, the Americans could fall back on the .50, which gave adequate, but not great, firepower.

I wonder what drove them to 'improve' an already working design resulting US not having a cannon until 50's. But well, it worked out of ok concerning the outcome but would have been great to see / fly cannon packed late war fighters for US.

Anyone has any idea on the rate of failure the american models of Hispano's had?

I suggest everyone to read this excellent article:

http://www.quarry.nildram.co.uk/CannonMGs.htm

Excellent read and a comprehensive answer to my question. Thanks Buren!

The troubled history of the American Hispano (from the same author):

http://www.quarry.nildram.co.uk/US404.htm

yeah, what everyone else said.

Its not the equivalent of professional motor racing where you go for the technically best possible option regardless of cost. there was a war on and the 0.50 cal was readily avaialble and did the job good enough against fighters.

Add to this the fact that American made 20mm were unreliable in high vibration and flex wing mount positions and too large for "in wing" mounting in existing US aircraft and its clear why they stayed with 0.50 cal.

This link about pattern bore-sight gun harmonization might give you some insight into the some of the issues.

http://www.researcheratlarge.com/Air...nBoresighting/

lolz, I read the part about the Russian guns carrying less explosives and such. That is displayed very well in IL2.....Ive flown the IL2M3 w/ those big 57mm wing cannons and also the LA5's and it became very obvious quickly that the Russian guns were simply not even remotly close to as powerful as the German/Allied guns. In game i also flew a Mig FS jet and had to unload basically all my ammo into 1 B17 to take it out. Also w/ the LA I ran out of ammo firing at 4 HE111s b/c the guns wuoldnt shoot em down. As for the British..or is it a French 20mm? the Hispano in the Spitfire, like 4-8 rounds downs a fighter and like 10-12 or so will down a HE111. As for the large caliber 50+mms I flew the Me262 UA w/ that 50mm and the Il2M3 w/ the 57mms and w/ the 262 it takes 1 or 2 rounds in the wing to kill big bombers, the Il2 its quite a few more. Im sure in RL it played out different but in game yeah....Russian cannons are kinda junky.

How good is your aim? :D The MiG-9 actually has very good cannons that do significant damage to the target aircraft. Several hits should be enough to finish off a B-17.

The Russians actually get quit a bit for their weaponry and there are a few other factors to consider that aren't strictly played out in the numbers.

The ShVAK 20mm cannon if we compare with the Hispano II fires at a higher rate (800 rounds per minute versus 600 rpm) and has a smaller round (20x99 versus 20x110) which means having a bigger ammo supply on the relatively small Russian fighters. Also if memory serves the ShVAK 20mm was very reliable through most of the war, even in dusty or dirty conditions whereas the Hispano had problems for years and it wasn't until later that the Mark II was made reliable.

Also the Russians have the best heavy machine gun with the Berezin UB 12.7mm.

I look at the three main cannons like this: The MG151/20 is a refined weapon with a very sophisticated high explosive MINE round. The Hispano is like a sledgehammer which fires the heaviest round at very high velocities. The ShVAK is more of a scalpel with high refire rate and good ballistics. Both ShVAK and MG151 can be fired through a propeller hub whereas the Hispano I don't think was ever fired from a synchronized installation.

Yes, the Shvak has higher rate, but it is also true that you need more hits to down a target.

So, it pretty much balances out in the long run as far as DPS (damage per second) goes, if we could assign a way to measure it.

I think that there's more to aerial gunnery than having the one round that does massive damage to a target with one hit. The mk108 does this, but i never use it unless i go against bombers. There are other things to consider, like for example ease of aiming, and i don't mean pure balistics (in which the 108 is still inferior to other lighter guns).

A gun with a high ammo supply and high rate of fire is easier to aim every single time, simply because you can afford to keep the trigger pressed a few more seconds and correct your aim by looking at the tracers. In this way, Russian guns with their high rate of fire could be easier to aim and score hits, compared to slow firing German heavy cannons.

On the other hand, having only fast firing light guns (like for example .303s) is very easy to take and correct aim, but commits you to a tracking shot, with all the dangers it brings due to target fixation.

I think that the "sweet spot" lies somewhere in the middle: a gun that fires projectiles big and powerful enough to cripple or outright destroy a fighter in less than 10 hits, while still being of low enough caliber to maintain a high ammo supply and high rate of fire to assist in aiming/correcting your shot. If the ballistics are good, it gets even better and that's why i like the MG151s a lot...it's like they are the golden middle ground.

You would like the modified 109F in this clip then :D

http://www.youtube.com/watch?v=0xj7Bd8BTMY

Lol .30 cal guns and smaller to me are like pickles and sauerkraut, they make me gag and throwup a little bit just seeing them mentioned......ive used them alot seeings how the Spitfire is my fav plane in IL2 and I can tell you idk how to kill anything with them. They are just barely enough to let the enemy know your behind them.......I once flew the Hurri MkIIB??(one with 12 30cals) against an empty B29 on unlimited ammo for like 20+ minutes and never shot it down before I was totally convinced that 30cals are useless and I wish I could get them off my planes. when I got done w/ that B29 it had sooo many bullet holes in it that when it got to base the ground crew coulda mistaken it for that months supply of ammo it had so many casings on it...prolly like 20,000+ rounds I put into it. Then I did the same thing to an He111 but not shooting it nearly as long but I still only shot that plane down when I think I killed the pilots. And the 30cals is my only real complaint with the Spit, good plane but its got 30cals. my next new favorite, finding out that 25 and 50% fuel makes a plane hella more manuverable is the Corsair F4U1C. I always liked the Corsair ever since I had a toy of it, it looks cool and after over a year of flying IL2 and keeping my planes at 100% fuel and seeing the Corsair as a flying rock and deeming it junk, I finally realized my awnser had been slapping me in the face all along. Soo, I lowered it to 50% fuel load and was actually able to make a Black Out inducing turn with out stalling...i was like..wow...its a mircle, low fuel settings do work....now that F4u1C is like almost my dream plane. It has good turn radius, its fairly fast and has 4 cannons.....its only problem is its engine overheats fast.

Just for the hell of it, I'll throw my $.02 in. Like the old saying goes: The most effective pistol round is the one in the pistol you actually have on you when the $hit hits the fan. The same goes for aircraft armament.

While I suppose there may be some merit in arguing this or that with power or effectiveness of various guns, the fact is that men go to war with the weapons at hand. In WWII they did so with devastating effect, just about every weapon arrangement used during the war killed people effectively when used advantageously by skilled pilots.

Much like the pistol analogy, the main thing that pilots (or any kind of soldier, for that matter) demanded from their armament was reliability, as evidenced by the quick demise of the Hispano on Spitfires during the BOB. This is one big parameter that we don't have in IL2, yet one of the most important.

All that said, I prefer whatever weapons the aircraft I'm flying has, so long as they work when I press the button.

All that is true but my definition of work is a gun that can kill the enemy quickly....dogfights are fast, and you dont have much time to aim and down targets before the next target appears or you got a guy on ur ass drilling you so I like guns that kill fast so I can get the kill, and move on. its sooo annoying when you shoot the shit out of something or someone and they dont go down so your stuck shooting them while someone kills you....and while in RL the 30cal was prolly an effective weapon in Il2 it sucks...imo it needs to be upped a little bit, its just a crappy gun. The only thing ive killed w/ a 30cal in less than every round I have was a Zero w/ a frontal engine hit from a Spit MKI. Ive downed a few other fighters but I think it was from either jamming the controls or killing the pilot from the front...but that takes awhile.

Set the MG convergence very short (I use 140m) and then fire from around that range, aiming for the wing roots, cockpit or engine of your target.

Even a Gladiator with 4 .303s or a Bf109D with 4 7.62mm MGs can bring down a lightly armoured opponent in a well aimed 2-3 second burst.

I suppose your right about the 303 not being very effective against aircraft, it was designed to kill people, it was never very good at destroying aircraft. I don't really think that the 303 in game is all that far off, it always took a steady hand and nerves to take down a bomber with them. It's been pointed out before that the value of sending a bomber home shot to pieces with half the crew dead or wounded may well be greater than a strait up loss, it's certainly just as good if the plane is written off and the crew is rattled to the point of being ineffective.

My point at any rate was that it was the "weapon at hand", nothing more.

The .50 (I'm talking about the round here) on the other hand was designed to penetrate tanks (albeit thinly armored ones), and proved to be effective at "tearing $hit up" including airplanes. I can't tell how many times I've had my 109 shredded by a single burst from a P51. The round is still used today to penetrate heavy targets and "tear $hit up".

The fact is that the .50 (and the excellent Browning machine gun that fired it) was also the weapon at hand and it did it's job well, given the targets it was asked to engage.

The problem is that the .50 did not do it's job well. It was adequate, but nothing more. Bout the USAF and USN wanted 20mm, the Navy so desperately that they were willing to ignore the reliability problems of the US-made M3.

For the USAF the problem was not so much lack of destructive power, as much as weight. They compensated for the lack of power of the .50 by adding more guns, but the Browning was a heavy gun (29 kg). In a plane like the Thunderbolt, it did not matter much, but the Mustang was really pressed to the edge weight-wise. If the Mustang had a Hispano in each wing, it would have had just a little bit less firepower than it did with 6 Brownings, yet would weigh roughly 100 kilo less (depending on whether we are talking Hispano II or V). Imagine a 100 kg lighter Mustang!

I'm curious. What makes disabled bomber getting back home with ½ crew better than it being shot down with entire crew MIA / POW? Or did I misunderstand?

Think about morale.

I have my convergence set to between 220 and 270...I play against AI and they usually dont let you get much closer then .30 away and still have a clean shot. Usually if they let you get .14 away im dodging the plane instead of aiming at it, trying not to slam into it haha. I guess maybe my convergence could be part of my problem.....I just put in a number that sounds good at the time and go with it. Also, I know the 30s can down lightly armored targets..i downed a Zero with a split second burst head on from a Spit MkI...I hit F3 for the fly by camera view and saw the Zero in the background flaming in a downward angle...was thinking to myself.."No way did a 30cal just kill something that fast" haha. I know close range helps w/ penetration but its hard to get to like 15 and below for me and still be aiming. If I get close enough like .15 it usually ends up in me getting greedy followed by a spectacular fireball.

I'd count losing pilot(s) that take quite some time to train / get experienced + the entire aircraft & rest of the crew worse that the alternative. Also returning even though damaged would raise confidence on the aircraft's ability to 'take us home' despite heavy punishment it received.. like B17 for example.

But what do I know, I wasn't there.

Online, if there are no helps on, with some practice and patience, its pretty easy to get to surprise people and fire on an unsuspecting bandit at a very close range. I always use max 150m convergence for wing guns myself, often as short as 120m. The closer the better... You know, when a 190 is the size of a P-51's (or P40/47/38's) gunsight, hes only 105m away, much closer than one might estimate. ;)

Would rather have 4 Hispano V with Tempest style ammo load-outs. At 42Kg each, you would have an armament that weighs 168Kg total, compared to 174Kg for 6 Browning M2s, yet it would have firepower equal to 12 M2s (Going by USN tests that value the Hispano as being 3 times as destructive as the M2).

Heck, you could have 6 Hispano Vs in a Thunderbolt (252Kg) replacing the 8 M2s (232Kg) for firepower equal to 18 M2s, or you could go with just 4 guns and a whole load of ammo.

I never had problems with the Thunderbolt's armament - just set the convergence at like 175 m, zoom on the sucker and let him have it. You can easily down 4 B29s aiming at the engines with extra ammo.

On a side note does someone know how frequent was the 6 gun installation on the Jug? There was an interview posted on simhq forums a very long time ago with a Jug pilot and he was surprised to hear that the 47 had 8 guns - he said they always had 6)

Aside from morale ...

One of the huge issues the US had in Iraq was better body armor and combat medics meant the proportion of casualties KIA was down massively which is clearly a good thing but the number of wounded shipped home and looked after in hospital for sometimes years after went up substantially.

Its the same logic that resulted in anti-personal mines designed to maim rather than kill.

As far as the 0.303 cal in game goes, if you attack an early war bomber (blenheim, ju88, he111) in a historically fashion - from the side above below or headon - you can get acceptable results. Admittedly the he111 is a touch more immune to 0.303 cal than most of the others but its still not hard to knock out an engine or even set a wing on fire.

This was discussed recently elsewhere.

Both 6 or 8 guns were standard options. the 8 gun option carried less ammunition to compensate for the weight of the extra browning and had other performance limitations. I think overall in real life 6 guns was usually preferred though I am not 100% sure on that.

In games of course people will go for 8 guns every time.

Really the P47 had 6 guns? Dang, I always thought it was the one plane that always had 8 guns haha. In Il2 its 50cals seem to be the deadliest, its either they are actually coded to be more deadly due to the ammo its got or its juist the weight of fire from its guns but ive got more instant kills w/ the P47s 8 guns then any other plane. its a good plane in game but its kinda stall like in dogfights and sharp turns....50% fuel makes it manageable atleast =D Lolz, also, has anoyone else noticed the D27 flies better then the D27 Late? My uncle and i experimented w/ planes and the P47s were one of them and my uncle noticed that the D27 Late liked to stall the most and handled the worst of them all....after he mentioned it I flew the different versions and kinda noticed it also.

I know for sure that all of the 4th Fighter Group Tbolts had 6 guns.
This is an example of a 6 gun 47. If you look closely you can see that the outmost gun ports are covered. No idea which particular fighter group this plane is from.
The six gun option was probably more common with the earlier variants of the Jug considering they had a more immature version of the engine, not sure about the details though. :S

My only real gripe with the Jug ingame that the 3d cockpit is subpar compared to all other examples. :(
DT should at least try to retexture/replace the gunsight, that orange blob is just plain ugly.

@WTE_Galway
Could you link to that discussion please? Many thanks.

It was spread through one of those endless "0.50 cal are nerfed" troll threads that popup over on UBI regularly.

I don't have it linked but do have some of the reference material linked from it, all of which mentions 6 and 8 gun versions but none say anything conclusive about what was used when and where:



P47 tactical trials:
http://www.wwiiaircraftperformance.o...-47c-afdu.html

Flight manual (unfortunately I think the preview of the trigger and gun section has been removed)
http://books.google.com.au/books?id=...page&q&f=false


P47 test flight journal from June 1943
http://findarticles.com/p/articles/m...g=content;col1

Buren, The outermost gun is covered with tape to protect it from debris. The other guns have condoms over them. This was a common practice.

@BadAim

Oh, ok. It looked way too similar to a model of a 6 gun example.

@WTE_Galway

Thanks. Going to check them out.

There's some debate as to 6 or 8 gun P-47s in wartime use. The standard configuration was 8 guns but P-47s were some of the most field modified aircraft so I wouldn't be surprised at the removal of guns for increases elsewhere.

It's the same code for the .50cals in the P-47 but having 8 definitely is more destructive than 4 or 6. I haven't noticed any difference in handling between the D-27 and the D Late. They are supposed to be the same with the D Late having a tweaked engine for higher performance (supposedly near M levels).

The P-47 can be flown successfully on some dogfight servers with only 25% fuel. That can also be offset by using fuel tanks plus the 25% fuel option. It handles much better without the extra fuel weighing it down. Like most US aircraft the P-47 carries substantial internal fuel and has better range than many of the German and Russian aircraft that have very short ranges.

Six or four, it was stunnishing. :grin:

http://www.youtube.com/watch?v=shsxu...eature=related