Centerline weapons vs wing mounted weapons.

And I too have never denied that their are certain advantages inherent in the physics of a centreline armament.
At the risk of sounding like a broken record,I do not believe that there is any data to suggest that this was the primary reason for the success of the Luftwaffe experten. If a statistical analysis were possible it may support a marginally higher success rate (it might not) none of us know.
The relatively higher success rate of thes German pilots can certainly be ascribed to many other factors over and above the style of their aircraft's armament.
Cheers
Steve

Wing guns don't really offer any great advantages to the pilot, at least none I could think of. I think even the designers of such planes as the P-47 and Mustang were well aware that (in general) the centerline armament is better. You work with what you got. And if your engine can't take an engine gun as with the radials and Merlins, than that option is out of the question. If your guns of choice don't come readily available in a synchronized variant as I think was the case with the Hispano, then the option of mounting them in the fuselage or wing root, too, is gone.

I guess you could argue that most planes with M2 Brownings could have been designed to have at least two of their guns in the fuselage, but most weren't. But that is usually a mere one third of your total firepower so they probably just thought "why bother?". If you have to put so many guns on your plane that 2/3 of them have to go into the wings anyway, the point of putting any into the fuselage becomes moot.

Come to think of it, it'd be interesting if there was a special reason for removing the early P-51's (and A-36's) centerline Brownings.

cimmex said:

I cannot see what you are debating here. Ask a sniper whether he would prefer a rifle were the sightline is close to the barrel line or one with sightline offset to the barrel. I think the answer would be clear. This is not a matter of belief but a matter of physical law and geometric .
cimmex

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A bit different problem isn't it?

One shot at ranges NO fighter pilot would seriously consider and at a rather tiny target vs dozens if not hundreds of rounds at a rapidly moving target of considerable size.

And NO sniper would consider using the same sight setting for guns of 2 or 3 different trajectories and flight times.

Look at the physical laws and the geometry. The long range shooting is a bunch of bushwah. A few victories were actually achieved at ranges over 400yds but darn few compared to the amount of "attempts".

Even the Germans gave the idea little credit. Absolute maximum combat range for the MG 131 at 6000 meters ( where the air is much less dense) was 1000 meters but the effective range against a bomber is given as 400 meters. In fact the only three guns the Germans list as having an effective range longer than 400 meters (against bombers) are the MG 151/15, the MK 103 and the BK 5. The first has an effective range of 600 meters and the last two 800 meters. Effective range against fighter planes is not given.

Here is an elevation and convergence diagram for the P-47.

http://www.zenoswarbirdvideos.com/Images/P-47/47GECD.gif

considering that the guns are not laser beams and there is some dispersion where are the "safe" areas for an enemy aircraft to be in those patterns? Granted at 100yd a 109 might be able to sit between the bullet streams (wings excepted) but at anything much longer it starts looking bad really quick. At 150yds the bullet stream centers are about 8 feet apart (with the 250 yd cross) and the 109 prop is how big? How long does it take for 8 unsynchronized guns to make a mess of the propeller? And if it is not a straight 6 o'clock shot? What does geometry tell us about the size of the target at off angles?

For planes with smaller props than the P-47 and guns closer together (and/or or using a 300yd cross) what does geometry tell us?

Or against bigger targets than a 109?

riacrato said:

Come to think of it, it'd be interesting if there was a special reason for removing the early P-51's (and A-36's) centerline Brownings.

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When tested by the British the synchronized .50s had a cycle rate under 500rpm. I don't know if this was on P-40s, P-39s or the Mustangs.

Center line gun at 450-500rpm or wing gun at 750-850rpm??? Rather butts right up to the centerline gun being worth twice what a wing gun is?

Well there's synchronizing and there's synchronizing. Iirc the M2 was sync'ed with a mechanical gear which as it seams cut down rof much more than the electrical method employed on the MG151 and MG131. And the centerline gun reference is usually made to the engine cannon which has the same rof as a wing mounted gun

True, but it may explain why the US didn't bother with trying to mount fuselage .50 cal guns for very long.

I can also certainly understand how the Germans might think that a single MG 151/20 through the hub was worth two 20mm MG/FFMs in the wings.

How many planes, and when, did the Germans have to make such an assessment? The 109Es had a gun in each wing but they were the MG/FFs. Very few "F"s were built with the single MG/FF through the prop. Enough to make an assessment? At least one "ACE" thought it was a retrograde step. 109 "F"s and "G"s with "wing" 20mm guns had them in the under wing gondolas. Dispersion problems? pitching problems (nose dips on firing)? The FW 190 doesn't "wing" 20mm MG 151s till when??

"pitching problems (nose dips on firing)" please explain how a cannon in the center or above of a prop axis can cause a nose dip? Nose dips are well known at the Hurricane with 40 mm wing guns because the recoil here acts below the prop axis
cimmex

my evaluation is a round from centerline worth ~1.75 from wings

Vincenzo said:

my evaluation is a round from centerline worth ~1.75 from wings

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What have you based that on?
Cheers
Steve

American pilots flying P39s vs lightly armored Japanese planes were notoriously unsuccessful. P38 pilots vs Japanese were successful. About the only thing those two planes had in common was centerline guns (twin vs single engine comes to mind), yet they had totally different success stories. The gun system then would appear to not be the determing factor in their success.

Soviet pilots flying Soviet centerline armed fighters did not have the same success as German pilots, flying either Bf109 (centerline) or FW190 (centerline and wing combo), so the gun system appears not to be the determining factor there.

Factors other than the gun system which affect success are numerous. Performance of aircraft vs opposition, (speed, climb, turn, acceleration, dive, stability as a gun platform, visibility, sighting system etc.) level of skill of opposition, numbers of targets available, weather, tactical situation, strategic situation, psychology of attacker and target......

109s had the option of adding wing mounted gondola cannons. Why? Needed more destructive capability?
109s went from 15mm to 20mm to 30mm centerline cannon. Why? Needed more destructive capability?

Taking the top performers from a data group is not statistically useable and certainly does not indicate a norm. It shows what could be achieved, but not what should be or generally was achieved.

It has been argued and agreed by many that the most effective weapon setup in WWII single engine fighters was four 20mm cannon. Since there is no way to centerline mount four 20mm cannon in a single engine prop driven fighter, it follows that the most effective gun system for a WWII, single engine, prop driven fighter, has to be wing mounted guns.

Besides, wing mounted systems are more flexible! (pun intended)

The LW fighters have enjoyed healthy performance advantage vs. VVS prior mid 1944, in ETO prior late 1942, in MTO from 1941-43. The P-38 was enjoying the advantage during most of the war in Pacific. OTOH, the Soviet fighters were in the opposite situation, the centerline armament can't help you if the enemy can exercise a 50 mph advantage. Same thing happened to LW fighters in last two war years, the centerline armament was not able to 'cure' the great gap in speed.

My point being that flatly stating that a layout of guns is the main fighter quality is misleading.

stona said:

What have you based that on?
Cheers
Steve

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just my opinion after years on this forum and years reading on WW2 airwar

cimmex said:

"pitching problems (nose dips on firing)" please explain how a cannon in the center or above of a prop axis can cause a nose dip? Nose dips are well known at the Hurricane with 40 mm wing guns because the recoil here acts below the prop axis
cimmex

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The gondola mounted "wing" guns might cause dipping making them less favored than the prop mounted gun.

claidemore said:

American pilots flying P39s vs lightly armored Japanese planes were notoriously unsuccessful. P38 pilots vs Japanese were successful. About the only thing those two planes had in common was centerline guns (twin vs single engine comes to mind), yet they had totally different success stories. The gun system then would appear to not be the determing factor in thier success.

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Actually the gun "system" might have a great deal to do with it as opposed to gun "placement".

The P-39 having a lousy gun "system " for fighter to fighter combat. The 37mm being very slow firing 2.5 rounds per second and a much different trajectory/time of flight than the .50s. Then the. 50s are slow firing sychronized guns and the .30s, again with a different trajectory/time of flight are waaaay out in the wings.

Vincenzo said:

just my opinion after years on this forum and years reading on WW2 airwar

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To which of course you are entitled

I think we all agree that the hard evidence to back up such an opinion is rather elusive. I don't believe that the advantage was anywhere near as large as that. Infact I'm not convinced that in the reality of air combat it was a relevant factor at all,but that is just my opinion too

Cheers

Steve

I think center - line because if you are hunting an enemy and your gun sight fails you want to have a better sense where the gun will fire and do more damage to the body of the aircraft. If you are hunting Japanese zeros and you want to destroy them fast you aim for the lightly armored wings which contain the gas tank. I personally would want a gun closer to me because technology is prone to fail no matter how high tech and you always need a back up I mean look at the F4 Phantom without a gun on some versions they would have been in trouble especially since those missiles were in their early years and tended to fail. My point is you want to have a sense of trust in your gun and you so to get the best result you want to have a gun closer to you. An example would be if you were to be shooting a target with a Tommy gun the wing mounted gun would be the gangster way to hold it on your hip you get virtually no accuracy the center - lined body is the holding it out straight out without looking at the ironsight not exactly accurate but much better performance than the gangster hip firing. Overall it depends on the situation.

J dog said:

...
If you are hunting Japanese zeros and you want to destroy them fast you aim for the lightly armored wings which contain the gas tank. ...

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Many of pilots being unable to hit a fighter, let alone in a desired part of a fighter?

this being exactly my argument, I doubt the location of the weps made much difference , the guys who could shoot would shoot well with either, the guys who could'nt shot well would'nt hit with either, hell of a lot more to firing from a moving aircraft than simply aiming with the sight!

to use the success of certian pilots as evidence of the effectiveness of centerline verses wing mount you have numerous factors to consider. as was said the enemies of a lot of those pilots were using the ac with the same armament configuration and didnt enjoy the same success. i am not going to take anything way from the german aces....in fact i admire them for being able to survive as long as they did. but by their own accounting there was a vast diffference between the eastern and western front as to the ease in which they got those numbers. in the early part of the war the vvs, though it out numbered the LW numerically, was vastly inferior in practically every other respect. it took them a long time to be able to match what germany was fielding, and by that time the LW ( and germany ) was on the decline. but if you look at the other side of the spectrum...where the LW met ac of comparible performance and under conditions that were either on par or favored their enemy they didnt enjoy the same type of success. in the BoB...things were pretty much equal and by design favored the RAF. the spit and the 109 were on fairly equal ground performancewise.....the RAF could land to rearm and refuel and be back in the air within minutes if need be. the LW pilots still ran several sorties a day over the uk. i would like to see the number of sorties flown by each side but would venture that they are pretty close to the same. so i think this would be a case where you could do a fairly accurate comparison. although i would personally prefer a plane with centerline arms...i dont see it playing a big factor in the BoB. the LW was not reaping the harvest that it wold in the east years later.

the length of air combat was measured in minutes. you had only enough ammo for very short battles. in the west, with few exceptions, the LW was able to fight, land, rearm and go off on another sortie. in contrast escort ac ( esp long range ac ) flew several hours to get into battle and then had to fly several hours back. the chance of having more targets with ammo available per hour in the air in this case decidedly has to go to the LW.

one more thing you have to consider is that LW pilots flew for the war...until they were killed, captured, wounded beyond the ccapacity to fly...or the war ended. us pilots flew for a set number of missions and rotated home. most were done within a years time. several like bud anderson, yeager, bong....signed up for extra tours. but this was the exception and not the rule. infact when anderson wanted to "re-up" they made him get a psych eval. like i said i take my hat off to the lw pilots...especially those that survived. the laws of odds and averages work both ways....gives them the chance for a lot of kills...but every time they go up is the possibility they wont come back due to a lucky enemy pilot, weather, mechanical failure...etc. that is a hell of a way to fight a war...

GregP said:

You doubters could be right, but I'm basing my opinion on the opinion of the top three aces off all time. Hard to say they're wrong ... unless you purport yourself as an expert beyond the top three aces of all time. I'm certainly not. I doubt anyone else is either, and that doubt fuels my contention.

If there are any aces out there who think otherwise, please chime in here ... along with your name and record.

Otherwise, I'll stick with the opinions of people who shot down HUNDREDS of other aircaft over modern revisionists who weren't ever in aerial combat in any capacity. The guys with the opinions WERE.

C'mon, get real. Yoy think YOU are better than Hartmman, Barkhorn, or Rall, then prove it with publically available figures.

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Ya'll getting a little overheated here. I don't see anyone here claiming to be better or more qualified than Hartmann et al, and to make such claims about people who are asking genuine questions is somewhat insulting, not to say condescending. What I don't see is hard data from anyone demonstrating that either configuration was better, given the myriad of different conditions and circumstances under which aircraft were shot down. For instance, at what ranges and deflections did the top aces normally achieve their kills? How many rounds fired per victory? Is there any information to suggest or show that Hartmann et al would have fared worse or shot down fewer aircraft had they been using fighters without centreline armament?