# Centerline weapons vs wing mounted weapons.



## davebender (Mar 8, 2013)

Found this historical tidbit on the Kurfurst site.


_In spite of our superiority of fire power over that of the enemy, many pilots would prefer the armament of an Me.109 with its one cannon firing through the airscrew hub and two machine guns mounted in the fuselage. They feel that despite its inferiority to our armament the concentration of parallel fire more than counter-balances our criss-cross pattern._

Wing Commander (Tactics) W.M. Churchill 
31 Dec 1941


----------



## Shortround6 (Mar 8, 2013)

Please note the words "They feel".

No test results, no experiments.

And in 1940-41 in controlled tests many British pilots were opening fire at ridiculously long ranges. Instead of the 300yd opening range that was asked they were opening fire at 800-1200yds. Shooting at 3-4 times the effective range of the guns sin't going to work no matter how they were arranged.


----------



## dobbie (Mar 8, 2013)

That is one big advantage, having your firepower in line with the fuselage. Especially if its something with good range. One big advantage to flying fighters like the P-38 is that with the weapons in the nose, there is no convergence to contend with, and some of the higher scoring aces made some pretty long ranged kills because of the concentration of fire.


----------



## davebender (Mar 8, 2013)

JG26 pilots flew both Me-109s and Fw-190As. That puts them in a good position to evaluate merits of wing mounted vs centerline mounted weapons. 

The unit must have written one or more technical evaluations of the weapons issue. Where are those reports?


----------



## stona (Mar 8, 2013)

davebender said:


> JG26 pilots flew both Me-109s and Fw-190As. That puts them in a good position to evaluate merits of wing mounted vs centerline mounted weapons.
> 
> The unit must have written one or more technical evaluations of the weapons issue. Where are those reports?



Why would they?

Any official report on the armament would emmanate from the Luftwaffe's armaments test centre.

If they were happy with the armament I very much doubt that such evaluations were made by front line units. Pilots may very well have expressed their opinions but that's all they are.....opinions. I don't remember a Bf 109 or Fw 190 pilot complaining about the standard armament of the various types,with the possible exception of the Bf 109 F.

Other problems were reported by units "breaking in" a new type to the manufacturer's engineers who would arrive with the new aircraft. These men reported to their employer who reported to the RLM (who were footing the bill).

In any case the armament is very similar. The guns mounted above the engine are effectively centre line on both. The Fw 190's inner wing weapons are firing through the propeller disc with minimal offset. It is only the outer wing weapons on both which would have much convergence. The only real difference is the cannon firing through the spinner of the Bf 109 (post E).

I heard Bader praising the centre line cannon on the Bf 109 F in an interview years ago. I have always suspected that there is a touch of "the grass is always greener....." about this.

The earliest 1940 gun camera footage from the RAF showed even worse results than those tests referred to by Shortround 6. Pilots were often opening fire at 1500 yards and underestimating deflection by at least 50%. In other words,whatever guns they were using,they had zero chance of hitting their intended targets.

Whilst it is true that some pilots did score long range victories with centre mounted weapons (I've seen those P-38 accounts too) the limiting factor on accurate air to air shooting was the gun sights. Every pilot who I've heard express an opinion says that the easiest/best way to shoot down an enemy aircraft was at close range and zero deflection. There was no huge improvement in gun sights until the gyro stabilised sights started to be fitted late in the war (at least for the RAF and Luftwaffe,don't remember what the USAAF was using).

Cheers

Steve


----------



## davebender (Mar 8, 2013)

Because Krauts believe in scientific management and that's doubly true for German military. They performed extensive tests on everything from camouflage value of field gray to accuracy of Ju-87 and Ju-88 dive bombers. Reports from these tests were typically just as thorough as tests themselves. So unless JG26 was manned by slackers there should be plenty of historical reports to read.


----------



## Shortround6 (Mar 8, 2013)

The "long range" shooting is pretty much pie in the sky stuff. Anything over 600yds needs an awful lot of luck. It happened, but being able to do it consistently is another matter. 

Consider the 117gram shell from a MG 151/20. It starts at 720m/s but by the time it gets to 300 meters ( 0.477 sec) it has slowed to 552m/s. This is still well within it's effective range. By the time it gets to 600 meters (1.10 sec) it is down to 422m/s velocity. depending on target this may still be in the effective range. However it is obvious that it will take another full second (if not considerably more) to make it to 1000meters. How far can the target aircraft move in just over 2 seconds?

Then you have the drop problem. The shell will drop 16 ft in the first 1 second of flight, this is allowed for by pointing the muzzle up slightly and the shell will cross the line of sight twice. once somewhere between 150-200 meters in front of the plane and once somewhere about 450-550 meters in front of the plane. The shell will never be more than a couple of feet from the line of sight. The problem comes after that, the shell (accelerating at 32ft per second squared towards the ground) will fall 48 feet in the 2nd second of flight. In order to get hits the pilot needs to _KNOW_ the _exact_ distance to the target, even 10% off isn't good enough. He needs to have the correct lead, even a 200mph bomber is covering 587 feet in 2 seconds. getting the speed wrong on a twin engine bomber by 10% means a complete miss. He needs to _KNOW_ the exact course relative to his own and he needs to _KNOW_ if the plane is flying level or descending or ascending. 
Tracers tell the pilot where he _SHOULD_ have been aiming 2 seconds earlier. 
The difficulty of getting hits goes up at something over the cube of the distance. Center line guns may have some advantage but it is nowhere near as big as some people make it out to be. 

It also helps if the guns have similar ballistics, the guns in the P-38 are a very good match, at least to 500-600yds so they may work well together a few hundred yards beyond that. The German guns ( some of the Soviet guns) had rather different flight times and trajectories from each other and are a lot harder to coordinate at long range no matter ho close together the muzzles may be. 

Pilots estimates of range are all over the map which doesn't help with analyzing combat reports.


----------



## GregP (Mar 8, 2013)

I beileve it is well documented that the top Aces like Hartmann, Barkhorn and Rall all preferred fuselage armament. They thought one in the fuselage was worth two in the wings. You'll note that virtually all modern fighters have fuselage-mounted guns, if they have guns.

Boy, Shortround, it's a good thing the pilots in WWII knew all that, huh?


----------



## Shortround6 (Mar 9, 2013)

And Hartmann, Barkhorn and Rall flew planes with wing mounted armament how many times in combat???? And what kind of of wing mounted armament?

"They _thought_ one in the fuselage was worth two in the wings"

I am not saying they didn't _think_ it. the questions are if they were right to think it or _why_ they thought it. 

I will note that "virtually all modern fighters have" _NO_ propellers and do not have to worry about synchronizing guns, and many modern aircraft guns would be difficult if not impossible to synchronize. 

I will note that "virtually all modern fighters have" rather large cannon and ammo feeds that are rather difficult to place in a wing.







I will note that "virtually all modern fighters have" no more than _two_ guns which means that there is no reason to stick them in the wings. 

I will note that "virtually all modern fighters have" cannon with much higher rates of fire than WW II aircraft cannon which means that they don't _need_ multiple ( as in 3 or more guns) to get the weight (or rate) of fire desired. 

I will note that "virtually all modern fighters have" computer assisted aiming systems and some even have a correction programmed into the fly-by-wire to prevent the gun recoil of an off-center mounted gun from slewing the plane off target. 

Gee whiz, at least 5 differences from WW II aircraft to "modern fighters" that affect gun placement. 

British WW II pilots (at times) were subject to some rather strange thinking by the "powers that be" which assumed that the average pilot wasn't going to be able to hit much anyway and had the planes set up for a "shotgun" approach to air to air combat. Guns were set up to point in slightly different directions to cover a bigger area of the sky but meant that seldom, if ever, would more than two guns actually hit in the same place unless the plane was at _very_ close range (and then each gun hit different parts of the target aircraft). Guns were also mounted to give "dispersion" patterns (loose mounts?) of 1/3 of degree or even 1 full degree (5 ft at 100yds) which while increasing the chances of a single hit, did absolutely nothing for getting a large number of hits.

One "official" pattern for the Spit MK VB has (at 100 yds) left hand outer MG hitting higher than the line of sight, the inner mg hitting low, the cannon hitting low but higher and just inside the the inner mg with the right wing guns being a close but not exact mirror image. Right hand 20mm hits lower than right hand inner MG. 
When superimposed on an He 111 silhouette from the 6 o'clock position at 250 yds the inner mgs overlap almost exactly at the bottom of the fuselage. the left 20mm is hitting the fuselage on the left side just over the wing root and the right 20mm is hitting the fuselage on the right side just under the wing root. the outer MGs are _missing_ the fuselage on either side almost at the level of the top of the fuselage. 
At 300yds the the inner mgs have crossed over and are missing (just) the bottom of the plane, the impact areas of the 20mm guns now form a figure 8 cented on the plane left gun upper circle and right gun the lower. the outer Mgs are no hitting the fuselage on each side about cockpit height. 
At 400yds the the outer MGs are now coinciding but just over the top of the fuselage ( impact circle overlaps a bit) the inner MGs are missing just under and inboard of the engines and the left 20mm is hitting the upper right fuselage and space and the right hand 20mm is hitting the left wing root. 

At no point do more than 2 guns of any type hit the same place. While this greatly increases the chances of hitting with _something_ it also means that no matter how good the pilot is he _cannot_ bring the full fire power of the Spitfire to bear on even a He 111 (from 6 oclock) let alone a single seat fighter. Please note that this has _NOTHING_ to do with the guns being in the wing as the guns could be adjusted to ALL hit the same point at one distance if so desired. 

Lets not confuse cause and effect here when talking about the benefits or problems of fuselage and wing mounted guns. 

For the Germans let us also note that there is a 100mps difference in velocity using the 92gm mine shell between a MG 151/20 and a MG/FFM and a 125mps velocity difference using the 115-117gm shells, the heavier shells retain velocity better than the light shells and are better for "long range shooting". 
Germans figured the heavier shell had a "max" range of 750 meters at 3000 meters altitude compared to a "max' range of 600 meters for the mine shell. Effective range for the mine shell was considered 400 meters _against bombers._

What were the German pilots comparing?
The wing mounted MG/FFM to the engine mounted MG 151? Wing mounted MG 151s to the engine mounted MG 151 (under wing gondolas?) Please note the under wing cannon are mounted a bit lower than the engine mounted cannon and have a vertical convergence problem as well as lateral. 
Fw 190 pilots with the early models had 20mm cannon firing at different velocities in the same plane. getting the MG 151s and the MG/FFMs to hit a fighter using a deflection shot when they had different flight times and needed different amounts of "lead" to hit the target may have been difficult?

Reactions: Dislike Dislike:
1 | Like List reactions


----------



## GregP (Mar 9, 2013)

Well, the three top aces combined shot down almost a thousand aircraft among them and I think their opinions are probably good ones. You obviously disagree. Want to know what they're comparing? Ask them. I don't know ... but around 1,000 planes shot down by three guys speaks volumes for their choice in my book, especially when they had a coice of whatever they wanted to fly and stuck with the 109. 

You and I don't have a great history of seeing eye to eye, do we? So, I suppose it's no surprise this time, is it?

Either way, looks like the fuselage-mounted armament idea has won out for SOME reason. Take your pick of why and welcome to it, no argument here. I have my own ideas why. Unsurprisingly, we have Korean War pilots give talks at the museum and they love the fuselage-mounted armament in the P-80 and F-86 way more than the wing guns in Mustangs, at least the ones who commented on it at all. Some didn't mention armament one way or the other, but had some good flying stories that were more interesting anyway. 

But, Gee Whiz ... you could be right ... if we all thought the same, it'd be a dull world.


----------



## Greyman (Mar 9, 2013)

It's always been known that centreline weaponry is better. There are plenty of reasons for WWII aircraft to have wing-mounted weaponry, but that doesn't change the fact that a gun centred with the pilot and gunsight is better than a gun three metres off axis.



Shortround6 said:


> Guns were also mounted to give "dispersion" patterns (loose mounts?) of 1/3 of degree or even 1 full degree (5 ft at 100yds) which while increasing the chances of a single hit, did absolutely nothing for getting a large number of hits.



You're always going to get a dispersion pattern, that's just the nature of the game. To what degree is the question. The mounts weren't intentionally loose, there are dozens of variables that cause a particular dispersion pattern size. 

Take eight Brownings in a Spitfire I to the butts and you're going to get eight different group sizes. Sometimes very, very different. The standard RAF 1/3 degree is a reasonable average of how the Browning .303in and Hispano 20mm would perform.


----------



## Shortround6 (Mar 9, 2013)

Greyman said:


> It's always been known that centreline weaponry is better. There are plenty of reasons for WWII aircraft to have wing-mounted weaponry, but that doesn't change the fact that a gun centred with the pilot and gunsight is better than a gun three metres off axis.



It is better, the question is, is it _twice_ as good?

for an answer we get "Ace ____________ (fill in the blank) SAYS so." which isn't really a very good answer. 





Greyman said:


> You're always going to get a dispersion pattern, that's just the nature of the game. To what degree is the question. The mounts weren't intentionally loose, there are dozens of variables that cause a particular dispersion pattern size.


 True. perhaps "loose" was not a good choice of word. The British could "apparently" adjust the dispersion pattern somehow though. They have hit diagrams for 1/3 degree and 1 full degree of dispersion. 



Greyman said:


> Take eight Brownings in a Spitfire I to the butts and you're going to get eight different group sizes. Sometimes very, very different. The standard RAF 1/3 degree is a reasonable average of how the Browning .303in and Hispano 20mm would perform.



I have shot enough guns to know that you would get different group sizes. You are also NOT going to get a 1/3 degree group without some sort of "help". Guns that were that _BAD_ on their own should have been junked or overhauled. 

The US used the very similar .30 cal Browning as a ground gun and the water cooled version on a sand bagged tripod could be made to shoot a 10 round group at 1000 inches (83 feet) with all ten bullet holes touching. It was almost a requirement that the guns do so in order for the unit machine gunners to pass their annual qualifications. Some of the suggestions for reducing group size don't apply to aircraft guns (like placing a tent stake behind the rear tripod leg to reduce vertical stringing) but suggest teh larger groups were not always the fault of the gun itself. 

A several inch (between 2 and 3) group at 83 feet does NOT equate to a 20 in group at 100yds. 

The "Spitfire Bullet Pattern 1" (which implies there was a No 2?) shows a 75% impact zone for each gun at about 3 feet at 200yds and a 100% zone of about 6 feet. It also shows the patterns at 100, 300 and 400 yds and where each gun _should_ hit (or miss) with a 350 yd convergence pattern. 

While a little dispersion is a good thing too much dilutes the possible impact. They were intentionally trading the possibility of getting more hits from poor shots for the inability of the better shots to get even the majority of their guns/bullets on target at any given time. 
They did the same thing with the quad .50 Naval AA gun. Each barrel pointed in a slightly different direction to increase the chances of getting hits, it meant that only one barrel of the four was actually "on target" at any given time and that not enough bullets could be put into a target to ensure destruction in a reasonable period of time, like several seconds on target.


----------



## tomo pauk (Mar 9, 2013)

About the 3 aces with 1000 claims: is there a reason to believe they would not accomplish the same with wing mounted battery? Put Hartmann in Spitfire IX and he will have no problems to score as he did.


----------



## Kryten (Mar 9, 2013)

centerline weps on a p38, me110 or Mossie or a whirlwind may have some advantage over wing mounts due to convergance, but on a single engined plane you have to factor in the reduction in rate of fire due to harmonisation!

secondly FW190 pilots had no difficulties with thier wing mounted armament!

Hartman racked up high scores because he was a top shot and more importantly a superb tactitian!
simple fact is very few pilots could even shoot straight , let alone accurately, top scorers were top shots, Beurling for instance pulled off some spectacular deflection and range shots with wing mounted weapons!


----------



## GregP (Mar 9, 2013)

Hi Tomo,

There's that theory, yes. Hartmann himself said otherwise. He was thoroughly familiar with the 109 and knew exactly what he could get out of it, and said that if has switched to an Fw 190, he might have been killed right away since he'd be a beginner in it. I'd tend to believe he'd feel the same about a Spitfire, but maybe not. In the war it wasn't an option, was it?

So ... it's a "what if" that I won't even take a crack at. We've had too many pilots give talks about planes and battles and express opinions that support the notion that center-mounted guns were preferred when available, even with the loss in fire rate due to synchronizer gear. I'll just take them at their word and let it go at that.


----------



## stona (Mar 9, 2013)

davebender said:


> Because Krauts believe in scientific management and that's doubly true for German military. They performed extensive tests on everything from camouflage value of field gray to accuracy of Ju-87 and Ju-88 dive bombers. Reports from these tests were typically just as thorough as tests themselves. So unless JG26 was manned by slackers there should be plenty of historical reports to read.



Have you ever seen a proper and rigorous scientific assessment written by a front line Luftwaffe unit about the standard fighter armament on the types they were flying?

The Luftwaffe had extensive test facilities and specialist test units to carry out that kind of duty. This was all done as part of an aircraft system's development,long before it went into service. Some of these units might ultimately test systems in combat,but they were not regular front line units as far as the Luftwaffe was concerned,that's why they were called things like "erprobungsgruppe" (even if the most famous one wasn't actually testing the aircraft it was set up to assess!).

There will surely be reports but not from JG 26.

Cheers

Steve


----------



## davebender (Mar 9, 2013)

> Have you ever seen a proper and rigorous scientific assessment written by a front line Luftwaffe unit


I've seen plenty written by Heer officers all the way down to company level. Luftwaffe more or less adopted Heer leadership methods so they probably write evaluations and after action reports too.


----------



## Greyman (Mar 9, 2013)

Shortround6 said:


> It is better, the question is, is it _twice_ as good?
> 
> for an answer we get "Ace ____________ (fill in the blank) SAYS so." which isn't really a very good answer.


I think people might be after different things. From a bean-counting, 21st century, internet-grognard, scientific point of view in which we're after a study stating '_a 109F centreline MG151 is 2.024 times better than a Spitfire Hispano-Suiza_' - pilot opinion certainly isn't the end all be all.

I always find pilot opinions fascinating, though. Pilot psychology isn't easily measured and in the final equation can be more powerful than a lot of scientific factors. 



Shortround6 said:


> True. perhaps "loose" was not a good choice of word. The British could "apparently" adjust the dispersion pattern somehow though. They have hit diagrams for 1/3 degree and 1 full degree of dispersion.



I'd have to see these diagrams to know what's up for sure. As far as I know adjusting group sizes for individual guns wasn't a 'thing'. I would assume it's measuring different group percentages. For example; 1/3 degree might be a 75% zone and 1 degree a 100% zone.



Shortround6 said:


> I have shot enough guns to know that you would get different group sizes. You are also NOT going to get a 1/3 degree group without some sort of "help". Guns that were that _BAD_ on their own should have been junked or overhauled.



Another reason centreline, engine mounted weaponry is better. A light-as-possible aluminum mounting isn't going to be as rigid as a one-ton engine or a heavy tripod sandbagged in the ground.


----------



## stona (Mar 9, 2013)

davebender said:


> so they probably write evaluations and after action reports too.



I'm sure they did but that's not the same thing as a comparative assessment of different weapon systems on different aircraft over which they had no control anyway.

In any case both the Bf 109 and Fw 190 had fuselage mounted weapons. I'm not sure what's to compare.

Front line units were equipped with aircraft with the standard armament for their role. They were limited in what alterations they could make. There are endless arguments about what they could or could not do but these are arguments about what those limits were,not whether they existed. 

Cheers

Steve


----------



## Shortround6 (Mar 9, 2013)

going in reverse order.



Greyman said:


> Another reason centreline, engine mounted weaponry is better. A light-as-possible aluminum mounting isn't going to be as rigid as a one-ton engine or a heavy tripod sandbagged in the ground.



Cowl guns are not mounted to the engine, so only one gun out of three is mounted on the engine. The engine is mounted on elastic mounts (rubber bushings) to cut down on vibration transmitted to the airframe. The through the prop gun may be rigidly mounted to the engine (or not):






French planes did mount the Hispano cannon on the engine. 

The "light-as-possible aluminum mounting" may not be aluminium. It has to not only withstand the the recoil but hold the gun in place while the plane does a 6-7 "G" pull out or turn ( 22lb gun is now putting 132-154lbs of load on the mount) wing gun mount is usually attached to the spar/s. Some later mounts incorporated spring buffers to reduce the recoil load. 

The point of bringing up the tripod is that the mounts can affect the accuracy or dispersion of the guns and we should not confuse the accuracy/dispersion of the gun itself with the accuracy/dispersion or the entire system. 



Greyman said:


> I'd have to see these diagrams to know what's up for sure. As far as I know adjusting group sizes for individual guns wasn't a 'thing'. I would assume it's measuring different group percentages. For example; 1/3 degree might be a 75% zone and 1 degree a 100% zone.



Three different diagrams are reproduced in Anthony Williams and Emmanuel Gustin's Book " Flying Guns of WW II". You may be right about the the group sizes but they don't appear to be exact fits. 



Greyman said:


> I think people might be after different things. From a bean-counting, 21st century, internet-grognard, scientific point of view in which we're after a study stating '_a 109F centreline MG151 is 2.024 times better than a Spitfire Hispano-Suiza_' - pilot opinion certainly isn't the end all be all.



We get into discussions of which airplane was better or which armament fit was better and the _fact_ that a Spitfire carried double the number of guns as a 109F or early G (without under wing guns) is often blown off by the 109 supporters with this tired "centerline guns are worth two wing mounted guns" excuse. When asked for proof we get "because ace XXXX says so". 

I don't need to know to 3rd decimal place the actual ratio of effectiveness  but something beyond "pilots XXXXX and YYYYY shot down a lot of planes using centerline guns so it must be true" would be nice. 

The whole long range shooting argument is a load of manure. 99% of the pilots flying in WW II had no business firing at more than 600 meters or so even at a 4 engine bomber flying straight and level. 

Success for them in such a situation depended the position of the stars, sun and moon, what they had for breakfast and how fresh the dog poo they stepped in on the way to the plane was.


----------



## Greyman (Mar 9, 2013)

Shortround6 said:


> Cowl guns are not mounted to the engine, so only one gun out of three is mounted on the engine. The engine is mounted on elastic mounts (rubber bushings) to cut down on vibration transmitted to the airframe.
> ...
> The "light-as-possible aluminum mounting" may not be aluminium. It has to not only withstand the the recoil but hold the gun in place while the plane does a 6-7 "G" pull out or turn ( 22lb gun is now putting 132-154lbs of load on the mount) wing gun mount is usually attached to the spar/s. Some later mounts incorporated spring buffers to reduce the recoil load.



Technicalities aside, you know what I'm sayin'. A centreline weapon would be much more stable. For example, a .303 Browning in a Gladiator fuselage was measured to have a 100% group of 10 inches at 100 yards, while a single Browning in a Hurricane was measured to be about 36 inches at the same distance. Or a .50 Browning from a Grumman F4F making a group 46 inches in diameter! Or, the worst of the worst (albiet a bit off topic); the waist mount in a Fortress/Liberator made a group size 126 inches in diameter. Ouch.

Compare that to a benched .50 - a mere 3.2 inch diameter.


----------



## GregP (Mar 10, 2013)

Hey Grayman, where'd you get the numbers? Just for reference, not questioning them.


----------



## Greyman (Mar 10, 2013)

All over the place (so the comparisons/conclusions I'm drawing in my post may not be a solid bet - different measuring standards). Most of my data on guns and group sizes comes from PRO documents in London, but even then the same party isn't taking all of the measurements.

For example, some random Squadron Commander writes up the paper for the Gladiator group, an official Air Ministry Tactics memo publishes the Hurricane data, a Navy rigging diagram for F4Fs provides the .50 cal data, and an Army Ordnance manual has the benched .50 numbers.


----------



## GregP (Mar 10, 2013)

OK, I can tell you from eprsonal experience that good groups are possible out to 1,000 yards.


----------



## stona (Mar 10, 2013)

GregP said:


> OK, I can tell you from eprsonal experience that good groups are possible out to 1,000 yards.



The problem in air to air combat is aiming a gun from a moving platform at another moving target. I've already made a post about the limitations of the gunsights used for most of WW2. The issues of various mounts simply compound the problem (as reflected in the larger groups for some) but are not in themselves the major problem.
A 1000 yard shot might be theoretically possible in a perfect scenario with zero deflection and I know that such claims were made. 
For the vast majority of aerial combat this kind of thing is as,Shortround6 said,pie in the sky.

Walther Krupinski echoed an opinion expressed by almost every successful pilot on all sides.

"When you are brave enough to get in close,then even closer still,waiting until you pull the trigger,you will succeed."

Advice taken to heart by one of his star pupils Erich Hartmann.

As an aside Dowding saw a possible advantage in raking or enfillade fire from turret fighters engaging bomber formations in the chance for the "overs" to be effective on an aircraft other than the intended target. I'm a big fan of Sir Hugh but that's optimistic

Cheers
Steve


----------



## vinnye (Mar 10, 2013)

I can see that there may be some advantages to centre line weapons - especially if the airdraft has a P38 / mossie type configuration - no problems with shooting through a prop etc.
But given that marksmanship was variable - not just due to skill but limitations of sighting systems and accuracy of or consistency of weapons used, a larger dispersal of guns may be advantageous?
This is why I would prefer - especially for a single engine type, wing mounted weapons - 6 or more 50 cals or 2 x 20mm cannons would do.


----------



## Ascent (Mar 10, 2013)

A question.

If the aces stayed with their aircraft type throughout the war then how do they know that it was better then something they didn't fly in combat?

I get the impression that they stayed with it because they knew it's capabilities not because it was superior, which they wouldn't know anyway as they hadn't flown the other type.


----------



## vinnye (Mar 10, 2013)

I suppose in the case of the LW, shortages of fuel to get air time with a different aircraft may make pilots reluctant to swop to a new aircraft.
If you had flown one type long enough to become familiar with its strengths and weaknesses - especially in combat, you amy want to stick with it so that when it matters - it does what you want / expexct it to?


----------



## tomo pauk (Mar 10, 2013)

The single engined plane with 6 x .50s can be a mixed blessing, depending on installed engine power. The half of dozen .50 cals weights some 470-480 lbs, compared to two Shvaks that weight 180 lbs, or two MG 151/20 at 190 lbs, or two Hispano II at 220 lbs. The USN conclusion being one 20 mm cannon is worth 3 HMGs. The engine power of 1000-1100 HP at 15-20000 ft (=P-40, F4F-4) might be hard pressed to struggle with additional 250-300 lbs? The wing mounted guns also need gun heaters (=added weight), unlike the guns that are close to the engine. The weight that far from centerline should also hamper the roll rate.
The large dispersal mean also that you hit with one or two HMGs, instead of 6 you've brought into fray. Dealing far less damage than necessary to really harm the enemy airplane.

For the US and UK single engined fighters, the question is more or less an academic one: neither engine (radials, Merlin, V-1710) was enabling the gun to be fired through the prop, the Hispano was not been able to fire synchronized, the big drop in rate of fire for the synch BMG (along with need to go for 6 of them) meant that such way of installing them quickly lost favor. The high power of new US engines (two stage Merlin, R-2800) also canceled out the effects of the higher weight of the HMGs vs. cannons, along with non-availabilty of a cannon that would be as flexible as German or Soviet 20mm.

The two Hispanos in the wing were demanding the back-up, in form of another pair, or 4 LMGs, or 2 HMGs - in case of jam, the another cannon firing would throw the fighter out of aim much more if that happened to the Fw-190 or La-5/7.


----------



## Shortround6 (Mar 10, 2013)

We know the guns and ammo could do it (good groups) so it is a question of the mounts. The question is if the spread, or a good part of it, was deliberate or not. While the wing twisting a bit while pulling a hard maneuver is easy enough to believe the idea that wing that is capable of 400mph+ dives and pulling 6-7 G turns is going to flop around like a cooked noodle when firing on the ground at the butts seems a little much. At least under the impact of .30 weapon recoil. Since the British (at times) had a deliberate policy of miss aligning guns it doesn't sound out of line that they didn't put much effort into reducing group size (although it seems they upper limits on group size?) even if they didn't "design" a mount that allowed the gun to wobble a bit.


----------



## Kryten (Mar 10, 2013)

The two Hispanos in the wing were demanding the back-up, in form of another pair, or 4 LMGs, or 2 HMGs - in case of jam, the another cannon firing would throw the fighter out of aim much more if that happened to the Fw-190 or La-5/7.[/QUOTE]

Actually the .303x4 or .50x2 was not there as backup in case of a jam, it was there to give the pilot options with what he engaged with, if you read through encounter reports considerable numbers of Spit pilots seem to fire the 20mm's alone then use the MG when ammunition ran out, the 4x.303 gave a far greater volume of fire and beaten area against soft targets when straffing, and I believe this is why they were often retained instead of the potentially more destructive 2x.50 setup!


----------



## stona (Mar 10, 2013)

Kryten said:


> Actually the .303x4 or .50x2 was not there as backup in case of a jam, it was there to give the pilot options with what he engaged with, if you read through encounter reports considerable numbers of Spit pilots seem to fire the 20mm's alone then use the MG when ammunition ran out, the 4x.303 gave a far greater volume of fire and beaten area against soft targets when straffing, and I believe this is why they were often retained instead of the potentially more destructive 2x.50 setup!



You are muddling your time line. The installation of two cannon and four .303 MGs on the Spitfire in 1941 _was seen,at the time,as a compromise _due to ongoing reliability issues with the cannon. The first squadron to try a cannon only armament found it so unreliable that they swopped their aircraft for some clapped out machine gun armed Mk 1s from an OTU.

This evolved into the B type wing. The C type wing also usually mounted only two of the possible four,now much more reliable,cannon and four .303 machine guns. These versions were a compromise only in that the .303 machine guns were far from ideal as aircraft became more heavily armoured.

As soon as .50 calibre machine guns became available in numbers (from the US) the RAF dropped the .303s like a hot potato and the later combinations of cannon and .50 calibre MGs,as seen in the E wing, were not a compromise but seen as an effective armament package and you are correct about that.

Cheers

Steve


----------



## Kryten (Mar 10, 2013)

I'm not personally convinced the position of the guns make a huge difference?
well lets think about the issue from a viewpoint that those of us who shoot can understand, 
first off range, the ballistic drop meant the pilot must estimate the range accuratly, 
dispersion, all guns suffer a degree of dispersion, some more than others even if ridgidly mounted, 
wind drift, wind creates dispersion and drift and wind speed at altitude must have a bearing on the matter, 
deflection , plane a or b are'nt stationary and being able to estimate range, speed and velocity of your rounds is critical 
Slip, is your aircraft or your target slipping at all, is it maneuvering to evade?
finally concentration, are you fixated on your target or in a borderline panic looking over your shoulder every few seconds!

put it in context and no wonder the aces said get in close, no matter either few aircraft that knew they were under attack were hit!

I often hear it said the vast majority of victims had no idea they were under attack!


----------



## GregP (Mar 10, 2013)

Hartmann and all the top aces flew all the aircraft. The top three (and more) simply decided they liked the Me 109's characteristuics better than the Fw 190. It probably had to do with familiarity rather than an absolute comparison. They liked the acceleration, rate of climb, and turning cahracteristics of the 109 better. If they had been ordered to fly the Fw 190, they would have done so, but they apparently had a choice. I've seen interviews with Hartmann years ago in which he said taht when the aces went to Berlin to receive decorations, they often flew the newest types of different aircraft and reported their observations to commanders or made their own choices if they were the commander.

In US service, almost nobody liked the P-47 at first, but they didn't have a choice. If the wing was re-equipped with them, they learned to fly and fight them as they gained experience in them. I'm sure there were units out there and people who preferred one type over another, but the commanders didn't have the leeway that top Luftwaffe commanders apparently did ... and the 109 was still in production. In 1945, if anyone wanted a P-40, it would have been from inventory, not from a new production line. When the war ended, the P-40 was no longer in front-line service, though it soldiered on until about 1958.

Later, many people loved the P-47, but you could hardly say it was "love at first sight."


----------



## stona (Mar 10, 2013)

Kryten said:


> put it in context and no wonder the aces said get in close, no matter either few aircraft that knew they were under attack were hit!
> 
> I often hear it said the vast majority of victims had no idea they were under attack!



Exactly.
Also eliminate deflection as much as possible. Some pilots were very good at estimating this,most were lousy. Until sights that did the sums for you came in the advice of all those aces and experten was good advice. It is impossible to over state the importance of a good gun sight. 
It is no accident that a significant percentage of aerial victories were scored by a minute percentage of the pilots flying. We still know most of their names today.
Cheers
Steve


----------



## tyrodtom (Mar 10, 2013)

I think the choices the Germans aces were presented with were not that they could chose the aircraft their unit flew, but that they would be reassigned to a unit that flew the type of aircraft they wanted to fly.
When Hartmann flew the Me262, he could have flown it in combat, as commander of a unit that flew it in Germany only, but he didn't want to abandon his comrades on the eastern front.


----------



## Kryten (Mar 10, 2013)

I did see a report on the increase in the number of successfull attacks once the gyro sight became available, but can't find it at the mo, I understand it made a considerable difference?


----------



## GregP (Mar 10, 2013)

Gunsights are VERY inportant. I have looked through WWII gunsights, an F-86 gunsight, and a functioning MiG-15 gunsight in a MiG-15-UTI. The difference between a mid-WWII gunsight and, say, the MiG is astounding. And the MiG's unit is very easy to operate by comparison as well.

I'm not surprised at all that a new gunsight would make a huge difference in the effective employment of a particular type.

I have not looked through a working WWII German gunsight, but have looked through and operated a late-war gunsight from a Bearcat. Gyro sights made a huge difference. For the worst, look at the stalks mounted on the nose of a Bachem Natter!


----------



## Greyman (Mar 10, 2013)

Kryten said:


> I did see a report on the increase in the number of successfull attacks once the gyro sight became available, but can't find it at the mo, I understand it made a considerable difference?



Recreation of '*Spitfire Combats: October 1944 to May 1945 - Comparison Between G.G.S. G.M.2 Results*'


----------



## CobberKane (Mar 10, 2013)

Maybe it would be worth sumarising the advantages/disadvantages of fuselage and wing mounted armament and seeing if everyone agrees:

Fuselage mounted - Advantages:
1. greatly reduces harmonisation issues (though this may remain an issue if differrent caliburs are used)
2. "Line of sight" aiming.
3. Concerntration of mass towards the centerline of the aricraft, aiding roll (more than ofset in twin engine designs by the weight of the engines!).

Disadvantages:

1. Reduced ammament carrying capacity (for single engine fighters)
2. Interuptor gear for cowl mounted weapons reduces rate of fire (ditto)
3. malfunction of or damage to interuptor gear can lead to prop being shot off (This was not hugely uncommon)

Wing mounted - Advantages

1. potential for more guns
2. reduced complexity 

Disadvantages:
1. Decentralised mass
2. dispersed fire (except at point(s) of harmonisation

Did I miss anything?


----------



## GregP (Mar 11, 2013)

I think the #1 is wrong. Different calibers are not an issue; different ballistics are. If they start with the same muzzle veliocity, the separation should be minimized well enough to make it not a great issue except at very long ranges.

Otherwise, you have a good summary except, the top aces ALL preferred centerline-mounted armament and they accounted for a great portion of the kills, so it had a demonstrated advantage despite any disadvantages. Today, since most jets have fuselage-mounted guns ... if they HAVE guns, the issue is sort of moot since cernterline or very close to it is the norm.


----------



## CobberKane (Mar 11, 2013)

GregP said:


> I think the #1 is wrong. Different calibers are not an issue; different ballistics are. If they start with the same muzzel veliocity, the separation should be minimized well enough to make it not a great issue except at long ranges.
> 
> 
> True - different ballistics would have been a better choice of words. I was thinking of the German use of the 30mm cannon here, or the American 37mm a la P39/63.
> I think the mass centralisation advantages of the centre mounted armament is an often overlooked factor. But when you say ALL the top aces preferred centre mounted armament, do you mean the German aces? Most of the allied aces (excluding the Soviets) flew fighters with wing mounted armament I would have thought.l


----------



## riacrato (Mar 11, 2013)

On the Fw 190: I think it's interesting to note that the inner four "centerline" weapons were grouped together on one button while the outer two were on the other. Iirc that stays the same even after the outer, too, are replaced with MF151 from A-6 model onwards.

That indicates to me the inner weapons were treated differently from the outer. Likely it was thought that when attacking the enemy from a distance or when at a different banking angle the chance for the outer weapons to actually hit were seen as low. I assume the outer weapons were only to be used when up close and at the right angle.


----------



## GregP (Mar 11, 2013)

Hi Cobber,

Yes you are right. All the top aces were German. I have a database with 11,054 people listed who have shot down an aircraft in aerial combat with a combined 133,068.8 individual victories and 4,862 shared victories. Of these, 9,146 men shot down 5 or more, making them "aces." The top 126 aces are all German with #127 being from Finnland. That would be Eino Ilmari Juutilainen with 92 victories. He is tied with two Germans. All of these aces are from WWII.

These top 126 WWII aces were awarded 17,404 victories among them with zero being shared victories. Hartmann, Barkhorn, and Rall had 928 victories among themselves and all flew the 109 out of choice since all had opportunities to fly the Fw 190. Barkhorn had a stint in 190's but the bulk of his victories were in the 109. If you add the next three guys, Kittel, Nowotny, and Batz the total rises to 1,690 among 6 guys. But Kittle flew both the 109 and 190 and I don't know how many he had in each mount. Nowotny and Batz had almost all their victories on the Eastern Front in the 109 (255 of 258 and 234 of 237 respectively).

So, here are 6 guys with 1,690 victories, with most being while flying centerline armament in the Bf 109.

I'd say centerline armament stands out as a major factor in air-to-air combat success.

In WWII, by comparison, the top three Australians had 52 vicotries; the top three Canadians had 67; the top three Finns had 221; the top three British had 88; the top three Italians had 62; the top three Japanese had 229; and the top three Americans had 112.

I don't know if the Finns were flying 109's or Buffalos, or if the Italians were flying centerline or wing armamment, but the rest were almost certainly flying wing armament with their success being significantly less than than the German predominantly centerline armament.

We can argue the merits of a target-rich environment on the Eastern Front, but their success was far and away better with their centerline-armament than anyone else flying wing-mounted armament. I won't engage in what-if the Germans had flown wing-mounted armament because that speculation didn't happen and nobody can say what effect it might have had with any degree of accuracy. One person's opinion is as valid or invalid as another in this.


----------



## stona (Mar 11, 2013)

Those statistics do not show that centreline armament was a major factor in air to air combat at all. They show many things not least of all the length of time that Luftwaffe pilots remained on active service rather than flying desks or training their replacements.
It might be more illuminating to compare the number of kills in relation to the total number of sorties flown,or even sorties in which the enemy was engaged,by the various aces.
Cheers
Steve


----------



## GregP (Mar 11, 2013)

Let's say we interpret things differently and not argue about it. Though I am a pilot, I'm not a fighter pilot.

The preferences of the top three aces of all times have been expressed in publically-available interviews and all mention centerline armament as a primary factor. I'll take their opinions any day over anyone's conjecture, but don't feel it is worth one single bitter word. So, I have absolutely nothing bad or sarcastic to say if you choose to believe otherwise. On the contrary, I look forward to seeing your conclusions. 

I think srties and action sorties are available for some guys, but far from all. If you have the information, perhaps you'd share it? Getting the information is the trickiest part!

Funny, my aerial victory list incluses a lot of information, but not the sorties and action sorties, the victim's aircraft type, or the victor's aircraft type. You'd think the people saving the data would include such basics, wouldn't you?

Cheers back to you, Steve.

Greg

Reactions: Like Like:
1 | Like List reactions


----------



## stona (Mar 11, 2013)

I'm not a pilot,but I was a chemist. Statistics is something scientists "do".
There's just too many variables to make any conclusion from victory lists that the style of armament has anything to do with success rates. I've already alluded to the sheer length of time that many Luftwaffe pilots remained in action compared to their allied counter parts. 
There are all sorts of other criteria which skew the results,the opposition,the tactical and strategic direction of the air battles would be two major factors. The statistics from the opening phase of Barbarossa make some interesting reading. I very much doubt the large number of Luftwaffe claims are due particularly to the style of it's two principal fighters' armament.
Centerline armament may or may not have been a factor in the success of some of these man but the statistics you are quoting absolutely do not demonstrate that.
As for over to me,I'm innocent until proven guilty. I need to see some statistics that demonstrate that centreline armament made Luftwaffe pilots more effective than their opposition and that I have not seen.
The "top three aces" are bound to praise the armament they had. What were they comparing it to? None of the Luftwaffe's front line fighters had anything else. 
Back to you 
Cheers
Steve


----------



## Shortround6 (Mar 11, 2013)

Center line armament may very well be more effective than wing armament. The question is, is it twice as effective? or 1.25 times or 1.5 times or _____ more effective. The twice as effective just seems a little too glib or pat of an answer.


----------



## GregP (Mar 11, 2013)

I'm an engineer and engineers do statistics, too. There ARE no statistics available for what we are researching. If you don't save the data (they didn't), there is little danger you can use it later to find trends and truths.

So we fall back on emperical evidence. The evidence is simple, the most successful guys in the role of fighter pilot used centerline armament with great success ... much greater than those who used wing-mounted armament. These same top pilots usually alluded to centerline armamenrt as being a big factor, certainly the top three did.

The Fw 190 is very tough to categorize as it had both centerline and wing armament. I know for sure that there is nobody out there who can say which armament fired the bullets that downed a kill, so I don't even consider the Fw 190 in either category as it fits into both with indeterminant results.

The Spitfire is ALL wing-mount as are the Hurricane, Mustang, P-47 and more. The Zero has both, but many planes have only centerline or wing-mount and not both. Yes, some versions of the 109 also had both centerline and wing-mount, but the top aces often removed the wing-mount guns, particularly in the F-model, and went with centerline. We KNOW Hartmann did so, even on some G-models he flew.

Take the top three 109 guys against the top three Spitfire, Hurricane, Mustang and P-47 guys. Include whatever planes you want.

None of the wing-mount planes came even close to the top three 109 guys. The USA's top two aces both flew centerline armament only planes (the Lightning).

Since we will NEVER have any statistics that show the armament placement versus action sortie victories or claims, we have to use the information we have to make judgements. I simply judge that the available evidence shows centerline armament was demonstrably better and was preferred by most of the highest-ranking pilots.

That's enough for me to agree with them until such time as some data are available that contradict the conclusion. To date, I haven't seen it, but am willing to look at any data to try to dispell the notion. So while I have decided and have an opinion at this time, I am open to changing my mind if and when sufficient evidence becomes available.

I hope the data surface, but hold out little hope for it since the war ended and 1945 and the data still haven't been uncovered yet by interested people who have been digging around for just such information. I believe the loss data are reasonably accurate as far as they go, but don't believe they are complete.

While I was working for Motorola I was the software liaison to the US Navy and ran the data colelction task for the Navy Standard Missile Depot Repair Program at Motorola. The Standard Missile is a 13-inch diamter missile that is either surface to surfce or surface to air. The Navy accounts for everything whenver an inventory is taken. I'll never forget working on a project to get all the back data together. I went over monthly reports for Standard Missile for more than 10 years, and came up with what looked to me like the most consistent data available.

Then we had a bomb dropped on us. One of the weapon stations got a new commander and he went around the base and ordered that it be cleaned up and made to look ship shape. They found two railroad cars just outside the base on an old siding of track that had been sitting there for at least five years and the locks were rusted shut.

When they cut the locks off, there were 15 Standard Missiles in containers, ready for deployment. Nobody knew how or when they got there and all had been listed as "expended in test" on the monthly reports, yet there they were, untouched in years, just off-base, in railroad cars. When the Navy has to account for the inventory, the inventory apparently gets accounted for whether they can find it or not.

Tell me the same and worse didn't happen in WWII anywhere out there in the confusion of the war and the immediate post-war data collection. Right ... So when the claims are reconciled with admitted losses, I still think somebody is either fibbing to make themselves look better or some data are simply missing. 

That's why I stick with the official victories awarded to the pilots by their own armed services ... I think it is the best data available to compare the pilots, planes, etc. against each other ... if the data are complete enough to track a particular thing. If not, then we'll never really know. All we have are combat reports and the views expressed in interviews ... usually with better-known pilots who distunguised themselves somehow in the conflict.

Probably there are people who agree with me; there are certainly people who don't, yourself included. I find the discussions interesting, and would not offer to say whether my take on things or anyone else's is more accurate. I don't think either of us will ever be able to prove our point to the other one. But I enjoy the challenge, the stories, and data uncovered.

Thanks for the links above to the RNZAF and RAAF above! I already have them stored on Excel along with all the other data I have accumulated. Now I just have to analyze them ...

Reactions: Like Like:
1 | Like List reactions


----------



## Milosh (Mar 11, 2013)

> None of the wing-mount planes came even close to the top three 109 guys.



Neither did the number of sorties.


----------



## GregP (Mar 11, 2013)

You have the sortie data for the wing-mount planes? Including both sorties and action sorties? 

If so, I'd be interested in seeing it.


----------



## Milosh (Mar 11, 2013)

Hartmann flew something like 1200 sorties and had combat in about 800.

Barkhorn flew 1,104 operational sorties.

Rall flew 621 combat missions.

You think Gabreski flew that many sorties in his P-47s and Spitfires?


----------



## GregP (Mar 11, 2013)

Depending on what sources you read, Hartmann flew between 1,400 and 1,425 sorties (1,404 is the most quoted number) with 800 to 850 being action sorties. He shot down 352 (claims) including 189 LaGG's, 81 P-39's, 25 Yak-9's, and the rest in descending order include 2 P-51's and 3 La-5's.

Barkhorn flew 1,104 sorties as you say, with 301 being action sorties.

I have Rall's total at "1,000+" sorties with 621 being action sorties, as you say.


Gabreski flew 166 action sorties in WWII and was credited with 28 air victories and 3 on the ground (shown but not counted in his total. I have no sortie total of other-than-action type. He had a futher 123 action sorties in Korea with 6.5 MiG victories. So his total was 289 action sorties, just short of Gerhard Barkhorn's. His 34.5 victories are the results of exactly what Barkhorn himslef in an interview.

I believe his words were to the effect: One reason for the high victory tally of the German pilots was oppurtunity. An Allied fighter pilot might fly 10 or more missions and not even see a German aircraft. The German fighter pilot, on the other hand, was never without a potential target around. Allied planes were everywhere. We simply had more opportunity and satyed in the fight until we won, lost, or died. That I survived was as much luck as skill. Enemy plaens were hunting us on every flight that was anywhere near the action.


----------



## CobberKane (Mar 11, 2013)

Hi Greg,
A couple of observations on your position that effectiveness of centreline armament is illustrated by fact that the highest scoring aces of the war (all German) used it. Firstly, I don't think you can so easily dismiss other factors such as the quality of the opposition as having much greater bearing on the scores of Hartmann et al - as can be evidenced by the fact that the LW pilots you've mentioned scored the great majority of their kills against opposition who were also using centerline armament - the Soviets. Correct me if I'm wrong, but I think ALL USSR fighters were thus armed, yet we do not see Soviet pilots scoring 300 plus kills against the LW. What prevented them doing so? Assumedly other factors such as quality of training, equipment and leadership - what have you. If these factors were disadvantages to the Soviets they were certainly advantages to the Germans. The fact that the top scoring LW aces were hugely more successful than their Soviet counterparts, when both used aircraft with centreline armament and similar firepower, suggests that other factors were the cause of the disparity in scores .
Secondly, while it is true that the USA's two top scoring aces flew the P-38 with centreline armament, it is also true that seven of the top ten US aces flew fighters with wing mounted armament. Johnny Johnson equalled McGuires score in aircraft with wing mounted armament, and Pat Prattle very likely exceeded Bongs score, with most of his victories coming in fighters with wing mounted armament (the balance being in Gladiators).
I think both systems had their advantages and disadvantages, but holding up the exploits of such as Hartmann as strong evidence of the overall superiority of centreline armament seems to be drawing a long bow.


----------



## Aozora (Mar 11, 2013)

It could also be argued that America's leading ace, one R Bong flew the P-38 with centreline armament, and most Russian aces flew fighters with centreline armament, including the P-39 etc etc. However, without some decent empirical data all the surmising doesn't really achieve much because there are far to many variables in air-to-air combat. For mine, until the advent of reliable gyro gunsights, the marksmanship and flying ability of the pilots was far more important to the outcome of combat than whether or not the armament was wing or centre mounted except, perhaps, at longer ranges.


----------



## GregP (Mar 12, 2013)

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. Otherwise ... centerline armament IS better since THEY say it is, not me at all. They are many times better than any other pilot who competed in WWII and lived to tell about it. They deserve the benefit of the doubt until it can be proven otherwise ... and you can't do that with any available data that I know of.

So ... you think what you want to think in good health. 

I'll do the same with the confidence that my opinion is in agreement with that of the top three aces of all time, and I'll be right until proven otherwise by anyone who shoots down 353 enemy aircaft and thinks otherwise by virture of having done so with wing-mounted armament alone. Tough since ALL jets have centerline armament, but someone may do it at some time. Ya' never know, do you?

There are NO data to prove otherwise anywhere that have been uncovered and made public that I know of. If you have it or know of it, PLEASE post it so we can be educated.

Argue with data or go away.

Any moderator, please tell me if I'm out of line here. If so, I retract all of the above and will refrain from further argument on this subject but still continue to think centerline is better without further comment from me in any form.


----------



## CobberKane (Mar 12, 2013)

Peace, Brother! I've got no problem at all with you sticking to your centreline guns. And you're right - I don't have any data to suggest the wing mounted weapons are better than centreline, any more than you have any data to suggest they aren't. The big three of the LW liked centreline weapons, though the fact that the Soviets had similar armaments without coming anywhere near matching Hartmman, Barkhorn, or Rall in kills sugests that other factors were responsible for the diference. The American/British experience seems to have been that the best pilots flying aircraft with both arrangements were equally successful. If aces like Hartmman, Barkhorn and Rall said they prefered centreline weapons I'm sure there were advantages they made good use of, but extrapolating their worthy opinions to a blanket conclusion that centerline weapons are better than wing mounted, full stop, seems a bit much. 
And mate, a 'revisionist' is either someone who criticaly examines the known facts, or someone who denies them. As I never denied anything, I'll assume you meant the term in the first sense - thank you!


----------



## DerAdlerIstGelandet (Mar 12, 2013)

Just keep it peaceful guys.


----------



## cimmex (Mar 12, 2013)

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


----------



## CobberKane (Mar 12, 2013)

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


 
Surely you're not going to deny me my God-given right to mount spurious arguments and arbitrarily gainsay other contributors?
Seriously though, there are a few more factors involved in arming a fighter plane than arming a sniper. If the superiority of centreline armament was a lay-down miserere, nobody would have been building fighters with wing mounted armament come 1945. To clarify my opinion, I think it was horses for courses. Some fighters, by design and intended purpose, lent themselves well to the centreline arrangement with it's attendent advantages. Others were better able to take advantage of what wing mounted armament offered. Many of course used both. So in that respect I agree - not much to argue about!


----------



## stona (Mar 12, 2013)

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


----------



## riacrato (Mar 12, 2013)

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.


----------



## Shortround6 (Mar 12, 2013)

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




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?


----------



## Shortround6 (Mar 12, 2013)

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.



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?


----------



## riacrato (Mar 12, 2013)

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


----------



## Shortround6 (Mar 12, 2013)

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??


----------



## cimmex (Mar 12, 2013)

“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


----------



## Vincenzo (Mar 12, 2013)

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


----------



## stona (Mar 12, 2013)

Vincenzo said:


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



What have you based that on?
Cheers
Steve


----------



## claidemore (Mar 12, 2013)

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)


----------



## tomo pauk (Mar 12, 2013)

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.


----------



## Vincenzo (Mar 12, 2013)

stona said:


> What have you based that on?
> Cheers
> Steve



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


----------



## Shortround6 (Mar 12, 2013)

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



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


----------



## Shortround6 (Mar 12, 2013)

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.



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.


----------



## stona (Mar 12, 2013)

Vincenzo said:


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



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


----------



## J dog (Mar 12, 2013)

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.


----------



## tomo pauk (Mar 12, 2013)

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. ...



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


----------



## Kryten (Mar 12, 2013)

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!


----------



## bobbysocks (Mar 12, 2013)

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...


----------



## Aozora (Mar 13, 2013)

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.
> 
> ...



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?


----------



## michaelmaltby (Mar 13, 2013)

Long range deflection shooting, or, up close and point blank .... in both cases you have to know what your guns will do ... wing mounted _or_ nose-centered.

George Beurling
Erich Hartmann - Wikipedia, the free encyclopedia

MM


----------



## stona (Mar 13, 2013)

Aozora said:


> 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.



Exactly the point I was making about 1000 posts ago. 

Cheers

Steve


----------



## Erich (Mar 13, 2013)

there was always plenty of confusion and crew opinions with the LW NJG's as to which was better, most likely having four weapons mounted in the belley to avoid blinding flashes as the cannons were fired - here though more conveniently located and center-line


----------



## GregP (Mar 13, 2013)

You may be correct Aozora. Perhaps I did get a little overheated. Apologies.

We have the top pilots in air combat that ever lived saying centerline was better and yet I see continued post of no evidence of same. Since there IS no database of objective data, we are left with emprical data from the experts, and they have already spoken their opinion. I'm just saying that their opinions should carry the weight of truth since they are, by anyone's definition, the most successful fighter pilots of all times.

I can readily admit they had more opportunity to score than anyone else ever did and also fought longer, which might account for the scoring disparity but, still, these guys would know what they're talking about if anyone ever did.

Obviously, not everyone agrees with that, and while perplexing to me personally, it is what it is; so be it. I doubt an objective database will ever exist that can satisfy some in here, but maybe it will surface eventually ... though I doubt very strongly that wing-mount armament will ever be popular again unless we go to single-engine turboprop attack planes. If we do, they'll probably not be used as fighters unles they get attacked themselves and do so out of self preservation, so any data generated from here forward will be heavily biased toward centerline guns of the rotary cannon type.

Wish we had a real database of all WWII victories, but while I have been trying to collect one for years, not all the data are available. My database to date accounts for 137,928.8 victories in all wars and 11,054 pilots, with 112,809.33 victories being from WWII. In fact, most victory lists don't even tell you what plane the victor was flying, much less what type the victim was. They usally have name, nationality, date, number of kills, and sometimes the unit. You'd have to research tens of thiousands of victories to get type of victor and victim and, while I'm quite interested, I'm not THAT interested and don't have access to all the data anyway ... IF it exists at all. We already know that for many German and Japanese victories, the data are simply missing due to war damage. I'd think the data for most British and American victories are around somewhere, but I don't know where to find the requisite documents to finish the data that are available and create a single list with the desired data points.

By the way, the 11,054 pilots is far from all pilots of military planes, but surely accounts for a decent percentage of those with an aerial victory over an enemy. Many pilots flew combat patrols and never saw an enemy plane, making their sortie not an action sortie though it was flown during a conflict.

Some in here have posted data that come from documents I have never seen and it might be nice to collaborate and come up with a good database. I'd be interested if someyone wants to exchange some information and perhaps proceed together.


----------



## vinnye (Mar 13, 2013)

Thanks for the link MM.
just read the Beurling part - very interesting. He was a hell of a pilot and marksman. Maybe not a team player but certainly a guy I would want on my side rather than the opposition!


----------



## Kryten (Mar 13, 2013)

when you consider the caliber of the opposition he was up against I think it even more impressive!


----------



## stona (Mar 13, 2013)

I don't see how the opinion of a handful of top scoring aces who never flew a contemporary wing armament in combat (say the .50 cals of the P-51 or cannon/MG combination of a Spitfire) can possibly be an informed judgement. You might call it empirical evidence by the literal definition,I might feel they are simply expressing a prejudice.

It is not good evidence that centreline armament was any more effective. I don't know whether it was or not,but nor did they or anyone else. Just because,with their minimal or zero combat experience of an alternative arrangement,those men intuitively felt that their centreline armament was better doesn't make it so. How do we know that,had they flown a P-47 in combat, they wouldn't have decided that four .50 calibre machine guns in each wing was definitely the way to go?

The only Anglo-American ace I've ever heard expressing admiration for centreline armament was Bader and that was in the context of the destructive power of the 20mm cannon firing through the spinner of the Bf 109 F. 
I don't remember hearing anyone one expressing the wish that they'd had a centreline arrangement over what they had."If only I'd had centreline armament I would have had 1.75 times as many kills",or something along those lines,though I suppose someone might have.

Cheers

Steve


----------



## michaelmaltby (Mar 13, 2013)

"... The only Anglo-American ace I've ever heard expressing admiration for centreline armament was Bader"

Aces are the least representative of the "issue". They are generally great marksmen and superior pilots. As such, they will get the kill either by stalking from behind or through exceptional deflection shooting (like Beurling). The reality is that as soon as design permitted (jets) the guns migrated onto the centerline - F-86 Sabre = P-51 Mustang. Hawker Hunter = Tempest.

The question should be, IMO ... which configuration was better for the _average_ pilot ..?

MM


----------



## GregP (Mar 13, 2013)

Hi Steve,

That's one way to think of it for sure. You make a good case.

I was under the impression that the top three guys got their ideas about centerline armament precisely by flying wing-mounted armament planes and shooting at towed targets ... and deciding which was more effective. All flew the Fw 190 and probably more, including American and British planes that were captured. I KNOW Hartmann flew P-51's .... don't know if he, in fact, fired at targets or not. I suspect so since 50-cal ammo was certainly available to the Germans. But ... that is conjecture on my part and you make a good case.

The "average pilot" part is certainly the case.

Exactly what data are you looking for that might surface to say which configuration would be better? Maybe some of it exists somewhere.


----------



## Erich (Mar 13, 2013)

in the LW case for day fighting it depended on the Allied fighter/bomber type encountered. by late 1943 the Fw A variants had proven superior to all Bf 109G types for engaging US 4 engines.


----------



## GregP (Mar 13, 2013)

That makes perfect sense becasue they were much more heavily armed than the 109 was and 4-engine bombers don't exactly evade anything, especially in formation, except maybe another 4-engine.


----------



## Greyman (Mar 13, 2013)

stona said:


> The only Anglo-American ace I've ever heard expressing admiration for centreline armament was Bader and that was in the context of the destructive power of the 20mm cannon firing through the spinner of the Bf 109 F.



The document referenced in the very first post that started this thread was on this very issue. Wing Commander Churchill toured three fighter stations and in the discussions that followed '_... it was notable that all five made the same comments ... and that their arguments and phraseology were almost the same ..._'

The pilots were:

Group Captain Broadhurst, DSO, DFC, AFC (Station Commander Hornchurch)
Wing Commander Rankin, DSO, DFC (Wing Commander Training, 11 Group)
Wing Commander Tuck, DSO, DFC (Wing Commander Biggin Hill)
Wing Commander Boyd, DFC (Wing Commander Kenley)
Squadron Leader Wells, DFC (OC 485 Squadron)

Definitely no slouches in the air combat department. Off the top of my head, in his book 'Lucky Thirteen', Wing Commander Hugh Godefroy DSO, DFC Bar, Croix de Guerre with Gold Star (Fr) praises the Fw 190's centreline armament over the Spitfire IX's.

I can remember reading many cases like this, from pilots of various nationalities and air forces; French, German, American, etc. It appears to me that it was widely accepted that a more centred position of of the armament was preferable, and that wing-mounted weaponry was a necessary evil for the aircraft that used it.

I can't recall of a single case of a pilot expressing a preference for wing armament over that of fuselage armament.


----------



## Aozora (Mar 13, 2013)

Interesting to note that when the Bf 109F became operational Adolf Galland and one or two other top German pilots expressed disappointment at the reduction in weight of fire, in addition to which Galland was concerned that the centre-line armament would present problems to the average Luftwaffe fighter pilot. As we know he highlighted these concerns by modifying a couple of F-2s, one incorporating wing armament and the other had 13 mm cowl guns.


----------



## tyrodtom (Mar 13, 2013)

The Bf109F2 only had a 15mm motorcannon, and 2- 7.92 machine guns, Galland's disappointment might have been in the lightweight armament, not that it was centerline.
Molders liked it.


----------



## CobberKane (Mar 13, 2013)

Maybe it would be reasonable to say that the advantages of the centreline armament (chiefly, line of sight aining) was appreciated by the pilots whereas the advantages of wing mounted armament (reduced complexity, potentially heavier firepower) favoured the designers. That's a pretty broad generalisation, I realise. The fact that Kurt Tank elected to mount the wing mounted cannon of the Ta-152 inside the propeller arc suggests he considered the added complexity of interruptor gear a good trade-off for the advantages of centre-mounted armament (or close to it).
The Ta 152 also compares well to later allied fighters in terms of outright firepower, thogh the diferring ballistics of its cannon may have been an issue.
On the other hand, by the end of the war British seemed to have pretty much setlled on 4x20mm wing mounted cannon as their optimum armament for single engine fighters, and I never heard of the pilots of Typhoons or Tempests complaining about ineffective guns. The USAAF fighters lagged behind a bit in this respect but as has been discussed elsewhere there were good reasons to stick with the lighter .5 cals
The fact that the pre-eminence of one armamanet layout other the other was not a settled thing after six years of war suggests to me that each had specific advantages, and designers chose accordingly depending on other design factors and the exact situations they expected their fighters to encounter in service.


----------



## tomo pauk (Mar 13, 2013)

The Ta-152-H was equipped with 20mm cannons in wing roots, as most of Fw-190. We could-should call those cannons 'center line' weapons? 
The Ta-152-C have had additonal pair of cannons under cowling, roughly where the Fw-190s usually had MGs. So we have here a centerline battery of 4 x 20 mm and one 30 mm?

The benefits of a centerline battery, consisting of one 15-20mm and two MGs would be overweighted by brute power of a quartet of 20 mm cannons, provided the plane has engine power to carry those?


----------



## stona (Mar 13, 2013)

tyrodtom said:


> The Bf109F2 only had a 15mm motorcannon,



I know that but Bader (in the TV interview from the 1970s I referred to) called it a 20mm cannon,which just goes to show how fallible human memory is.
Steve


----------



## CobberKane (Mar 13, 2013)

tomo pauk said:


> The Ta-152-H was equipped with 20mm cannons in wing roots, as most of Fw-190. We could-should call those cannons 'center line' weapons?
> The Ta-152-C have had additonal pair of cannons under cowling, roughly where the Fw-190s usually had MGs. So we have here a centerline battery of 4 x 20 mm and one 30 mm?
> 
> The benefits of a centerline battery, consisting of one 15-20mm and two MGs would be overweighted by brute power of a quartet of 20 mm cannons, provided the plane has engine power to carry those?


 
Given that the wing-root cannon of the Ta 152/Fw 190 shared the advantages (eg closer to the line of sight of the pilot) and disadvantages (eg need for interruptor gear) as cowl mounted weapons, I would be inclined to include them in the centreline catagory for the sake of discussion. After all, even the cowl and hub mounted weapons were offset from line of sight to some degree. What were the last fighters to use true line of sight weapons? Probably something like the Sopwith Pup!


----------



## Milosh (Mar 14, 2013)

The SPAD XII fired a 37mm shell thro the center of the prop shaft.

The Hispano-Suiza aviation engine had to be geared to allow the gun to fire through the propeller shaft.


----------



## spicmart (Mar 14, 2013)

The Ta 152's wing root cannons are 25 cm farther away to each side from the centerline than the guns of the Fw 190, due to the extended wing.
I guess one could still call it within the centerline grouping though.


----------



## riacrato (Mar 14, 2013)

stona said:


> I know that but Bader (in the TV interview from the 1970s I referred to) called it a 20mm cannon,which just goes to show how fallible human memory is.
> Steve


I think the comment from tyrodtom was more in response to Aozora. One should not forget that the first F models were either equipped with the MG-FF or the MG151/15. Those were markedly less powerful than the MG151/20. If Galland's comments were in response to the armament of the very first Friedrichs (and I think it's kind of likely he was referring to the F-2) then the situation changes with the introduction of the F-4. For what it's worth Anthony Williams estimates the 20mm MG151 to be about twice as powerful as the 15mm version.


----------



## riacrato (Mar 14, 2013)

spicmart said:


> The Ta 152's wing root cannons are 25 cm farther away to each side from the centerline than the guns of the Fw 190, due to the extended wing.
> I guess one could still call it within the centerline grouping though.


I think so, too. But as a note: Unlike the cowl guns, which fired parallel to each other, the wing root guns were zeroed along both axes iirc (so y *and x*).


----------



## CobberKane (Mar 14, 2013)

Milosh said:


> The SPAD XII fired a 37mm shell thro the center of the prop shaft.
> 
> The Hispano-Suiza aviation engine had to be geared to allow the gun to fire through the propeller shaft.


 
I remember reading about that. it was single shot and the pilot had to reload by hand. Those were the days when men were real men, women were real women and small furry creatures from Alpha Centuri were real small furry creatures from Alpha Centuri...


----------



## spicmart (Mar 14, 2013)

riacrato said:


> I think so, too. But as a note: Unlike the cowl guns, which fired parallel to each other, the wing root guns were zeroed along both axes iirc (so y *and x*).



This seems obvious. But is there a quote about this anywhere?
I also wonder if the cowl guns were aligned to meet the motor cannon's line of fire (y-axis)?


----------



## GregP (Mar 14, 2013)

From years of reading about WWII aircraft (no particular reference stands out), I recall that any particular aircraft could be zeroed like the pilot wanted it. There might have been "standards" (very likely) but, in the field, the crew chiefs pretty much did what the pilot asked of them when it came to customizing his aircraft ... assuming anythig like a decent relationship. Most pilots tried very hard to have a good relationship with their crew chief; after all, his work could save their lives.

I have read that some pilots in the Bf 109 wasnted the guns parallel to one another and some wanted convergence at some distance. The gun mounts would allow either. It is worth remembering that even if they converged at, say 400 yards, then they were no farther apart at 800 yards than where they started, so it wouldn't make all that much difference unless the convergence was pulled in significantly.


----------



## riacrato (Mar 15, 2013)

Exactly. With cowl guns being that close together and, more importantly, that close to the sight, the inherent spread caused by the gun, its mount and the vibrations of the aircraft will likely make any convergence on the x axis rather cosmetical.

As for a quote. I remember HoHun had the original documents for the convergence setup. I think he's banned here though.


----------



## tomo pauk (Mar 15, 2013)

HoHun is not banned, but left after a heated discussion.


----------



## stona (Mar 15, 2013)

There were far more fundamental problems with air to air gunnery than the arrangement of the weapons. Whether one arrangement was or wasn't marginally better than the other would have had a minute effect on the outcome of most combat.
Here is an 8th AF report on the P-47. I can post it because it is easy to find on my computer. If I was at home I could post similar reports from just about every combatant air force in the ETO from throughout the war.







Cheers

Steve


----------



## Readie (Mar 15, 2013)

Pretty much sums it up Steve.


----------



## GregP (Mar 15, 2013)

Steve, What is the date of that report? Is it early in the war with green pilots or is it late 1944 or later? It is certainly understandable early in the war. If late, the question is why the air-to-air gunnery training level isn't better. Also, if they were firing at towed sleves then I understand how they can know the real range. But if this was based on combat reports, then the writers weren't there and could not possibly know the real range. Makes me wonder.

Can you tell us what report by number this came from and where you got it? Please understand, I'm not saying it is wrong in any way at this time, just wondering how and when they got the data. 

As I understand it, green pilots typically opened up at long range while the veterans usually closed to a good distance before ever firing the first shot. It's one reason why green wingmen were usually assigned to veteran flight leads ... so they would learn both when to start firing and proper tactics. All air forces did that with the Germans starting it in the Spanish Civil war, at the start of WWII. The practice started in WWI, when ALL pilots were pretty green out of flight school.


----------



## stona (Mar 15, 2013)

It is from this document.






It was authorised for reproduction in October 1944 and was written post D-Day as it covers the period after the invasion into the third quarter of 1944.

I imagine the author(s) had good access to all the intelligence they would require in the writing of the report.

Cheers

Steve


----------



## Greyman (Mar 15, 2013)

GregP said:


> Also, if they were firing at towed sleves then I understand how they can know the real range. But if this was based on combat reports, then the writers weren't there and could not possibly know the real range.



Gun Camera.


----------



## CobberKane (Mar 15, 2013)

The report is obviously referring to combat encounters and is comparing gun camera analysis to combat reports. Pilot X says "I opened fire at 300 yards..." whereas examination of silhouette of the target with reference to the borders of the film shows the range was actually 600 yards. Given that the report apparently refers to a time when the USAF was in the ascendency, we could draw a couple of conclusions:
1. It is extremely difficult for even well trained pilots to hit anything at 600 yards or more
2. Given that pilots were routinely underestimating range by a factor of 50%, and this was the cause of them miss-aiming, the results would have been the same with either centreline or wing mounted armament
This does not give lie to the assertion that experienced pilots might find value in the centreline arrangement at more reasonable ranges, as Greg pointed out. But sticking a hub mounted cannon on a fighter probably wasn't go enable even well trained pilots to start sniping opposition half a mile away.
What ranges did Bong, Macguire and other P38 aces typically fire at? 
PS. Great doco, Stona. More please!


----------



## GregP (Mar 15, 2013)

Thanks Steve, Since this was mostly pre late-1944, the problem was most likely green pilots. I'd bet this situation rapdily changed as they got seasoned ... at least one would HOPE so.

I have seen enough gun camera film to know that estimating range with the film was not an easy task, by any means. You could be right and, if so, then the "real" range was ± quite a bit and this was a case of "armchair quarterbacking" by the intelligence guys as feedback to the pilots. I don't know about any of you but while I was learning to fly, the right altitude for flaring for a landing was something you learned only by doing it. Once you learn, it sort of gets to be second nature and you don't even think about it when you land. 

I'd venture to say learning to shoot at an enemy plane would be much the same. I've only done it with lasers in a Beech T-34 but, I learned quickly. It would seem to be the same with bullets ... except for learning the bullet drop and speed difference ... which it seems would be easily learned from shooting at towed targets with the occasional tracer for feedback. I'd bet the same study done in the first quarter of 1945 would have given significantly better results with mostly the newer, green pilots shooting at longer ranges. 

But I also don't have the 1945 study to prove that ... just conjecture, which is worth what you paid for it. Thanks for the neat stuff Steve!


----------



## CobberKane (Mar 16, 2013)

Apart from anything else the report kinda gives an insight into how hectic air combat undoubtedly was, doesn't it? The pilot's sense of time and distance were completely warped. Not only did other aircraft seem to be half the distance they actually were, but there seems to be a discrepancy between the length of fire the pilots loosed and how long they were really firing - that is, if the combat reports were typical of the ones I've read, where bursts are usually recorded in multiples of seconds rather than the fractions of seconds spoken of here. As any cop knows, take the recollections of a. High stress situation from even the most well meaning witness with extreme caution. Also emphasises what a game changer the K 14 sight must have been for the average pilot by giving him some terms of reference in such a fluid environment.
Greg, re the experience of the pilots I this report - surely post D-day the USAAF would have been fielding a good mix of experienced pilots and well trained newbies? The report indicates that one third of engagements resulted in the destruction of the enemy, which seems like a pretty solid strike rate. And knowing the size of the film frame and the target getting a good idea of the range should have been a matter of maths rather than estimation


----------



## Juha (Mar 16, 2013)

riacrato said:


> I think the comment from tyrodtom was more in response to Aozora. One should not forget that the first F models were either equipped with the MG-FF or the MG151/15. Those were markedly less powerful than the MG151/20. If Galland's comments were in response to the armament of the very first Friedrichs (and I think it's kind of likely he was referring to the F-2) then the situation changes with the introduction of the F-4. For what it's worth Anthony Williams estimates the 20mm MG151 to be about twice as powerful as the 15mm version.



IIRC that wasn't the case, Galland was refering the spread and was in oppinion that the closely grouped armament of 109F suited well to good shooters like Mölders but not to majority of LW pilots who were rather poor shots. He wasn't the only LW Experte who thought so, e.g. one of the top JG 54 aces, IIRC Philipp, admired Hurricane's wing armament when he and some Finnish aces, who prefered, like most of Finns and Soviet pilots, fuselage mounted armament, talked about different armament layouts.

Juha


----------



## J.A.W. (Mar 17, 2013)

While Spitfires P51s were fitted with the gyro-gunsight by `45, the Tempest was using a 40s HUD - with the old reflector image being projected directly onto the bullet-proof glass windscreen. Judging by those cine-shots of the Tempest in air-to-air combat, the ability to direct 4 20mm Hispanos on target didn`t seem to be much of an issue, it was really a question making sure the target was there when the shells arrived,either by fancy hard turning hi-angle deflection shots, or burrowing up his arse letting fly with the lot..
I have had a fairly close look at the 4 20mm [Shvak?] front fuselage La 9 set-up, it looked meaty enough..but was it any better than the Hawker set-up?


----------



## stona (Mar 17, 2013)

J.A.W. said:


> Judging by those cine-shots of the Tempest in air-to-air combat, the ability to direct 4 20mm Hispanos on target didn`t seem to be much of an issue, it was really a question making sure the target was there when the shells arrived,either by fancy hard turning hi-angle deflection shots, or burrowing up his arse letting fly with the lot.



Well it was a serious problem for all combatant air forces of the period. 
Most pilots were simply not capable of estimating range,let alone angle off,accurately and stood no chance of hitting anything using your first method. Noteable deflection shooters like Marseilles or Beurling (who favoured both methods) are remembered by name today. 
Very few pilots had the ability or were brave enough to adopt your second method. Again the Baders and Hartmanns are known by name and method today.
These problems are referred to throughout the war in various analyses.
The RAF invested much time and effort trying to improve its pilots ability to make better judgements,I have a series of gunnery manuals somewhere which include various excercises to be completed. I'm sure the others did the same.
Cheers
Steve


----------



## stona (Mar 17, 2013)

GregP said:


> Thanks Steve, Since this was mostly pre late-1944, the problem was most likely green pilots. I'd bet this situation rapdily changed as they got seasoned ... at least one would HOPE so.


By the time of the report,late 1944,post D-Day,there was less than six months of the war left! The P-47 had been active in the ETO for nearly eighteen months. Whether there was any improvement in the last three months of the war in 1945 would be a moot point.
Cheers
Steve


----------



## tyrodtom (Mar 17, 2013)

The flying up their butts method had a downside too, Hartmann crash landed 14 times, most of those crash landing was from damage caused by flying through his victim's debris. And there was also many times he had damage that didn't result in crash landings, but made it necessary to return to base early.
Hartmann knew the risk that went with his method, and considered the results justified the extra risk, but not everybody might feel that way after several crash landings and escapes.


----------



## GregP (Mar 17, 2013)

Hi Steve, I intended to say the pilots should have been better from about the last quarter of 1944 onward. So that would be from October 1944 through May of 1945 and that is about the last seven+ months of the war in Europe. I'd guess if they weren't better by then, they wouldn't be getting any better regardless of experience. In any case, after summer of 1944, the US pilots SHOULD have been better than during their first year and half of war.


----------



## stona (Mar 17, 2013)

GregP said:


> Hi Steve, I intended to say the pilots should have been better from about the last quarter of 1944 onward. So that would be from October 1944 through May of 1945 and that is about the last seven+ months of the war in Europe. I'd guess if they weren't better by then, they wouldn't be getting any better regardless of experience. In any case, after summer of 1944, the US pilots SHOULD have been better than during their first year and half of war.



Well yes,you'd hope so 

Don't forget that,unlike the Luftwaffe anglo-american pilots served limited tours and tended to rotate out to fly a desk or train their successors.

I think that the good,agressive and competent combat pilots just got better and more lethal whilst the vast majority bumbled through hoping to survive. It is remarkable that so many aerial victories were achieved by a relatively small percentage of the men flying.

I remember a BBC documentary,shot in the early 1970s,which traced some of the BoB pilots. Some had become household names (Lacey,Bader etc). One old squadron leader made no secret of the fact that he knew that he commanded several men who never shot anything down and whilst not accusing them outright of cowardice made it clear that he knew that they would not take any risks. One old fellow admitted as much. This is not an implied criticism,by me. I don't have the right to judge,unlike that squadron leader. We are not all cut out to be heroes though me may also serve.

Cheers

Steve


----------



## Kryten (Mar 17, 2013)

GregP said:


> Thanks Steve, Since this was mostly pre late-1944, the problem was most likely green pilots. I'd bet this situation rapdily changed as they got seasoned ... at least one would HOPE so.
> 
> I have seen enough gun camera film to know that estimating range with the film was not an easy task, by any means. You could be right and, if so, then the "real" range was ± quite a bit and this was a case of "armchair quarterbacking" by the intelligence guys as feedback to the pilots. I don't know about any of you but while I was learning to fly, the right altitude for flaring for a landing was something you learned only by doing it. Once you learn, it sort of gets to be second nature and you don't even think about it when you land.
> 
> ...



Laser travels at the speed of light in a straight line, cannon shells and bullets are a very very different proposition, If your flying straight and level behind your target you need to be able to estimate the range, adjust your solution and fire, , the arc of the round dropping onto the target in the ideal world!
In reality there are huge differences to take into account, if your pulling even the slightest g you not only have to estimeate range but lead as well, if you and your target are pulling g you have to estimate, range, relative speeds, lead (deflection) and any slip or rudder coordination to keep your sights where you want them!
now consider firing at a target that is turning rapidly and you may well be estimating the whole solution and the targets position as it is under your nose and out of sight!

I shoot regularly, I have shot heavy weapons on moving vehicles during my military service and I have used lasers in excercise, the laser makes things laughably easy compared to firing real ammo!

some top pilots no doubt had the instinctive skill to shoot accuratley, most it would seem however did not!


----------



## GregP (Mar 17, 2013)

All those things you said are true and I shoot fairly regularly, when I get the chance to do so, too. I think learning to shoot at towed targets will teach the lead and coordination required when shooting at airborne targets ... and then the pilot has to learn to hit manuevering targets once he can hit towed targets. Maybe I think that because I know several former fighters pilots who all said the same thing, and that's the way they did it. First shot rifles, then skeet, then towed targets and then mock dogfights with cameras rolling. Finally combat, if it happened during their service careers. If not, they still practiced shooting at towed and stationary targets on the ground. 

Seems like the guys who had the most fun were the A-10 drivers since they were encouraged to stay down in teh weeds and fly near the limits. They got in a lot more hours than the F-15 / F-16 drivers, and were very happy to dogfight with anyone who would come down and play.


----------



## bobbysocks (Mar 17, 2013)

GregP said:


> I have seen enough gun camera film to know that estimating range with the film was not an easy task, by any means.



a question to guys who used to process the combat film and took care of the gun cameras was...did the image in the film represent what the pilot saw or was it magnified for gathering information? did the pilot see the plane exactly that big when he fired or was it much smaller in actuality? i never did get an answer. the magnification of the lenses and the speed of the film may show the plane closer and slower than it really was....


----------



## GregP (Mar 17, 2013)

Good question! I think you may find some magnification and slowed film rate so the people can see what is going on. Some of the ones I have seen are definitely slowed down, but I merely suspect the magnification.


----------



## CobberKane (Mar 17, 2013)

Regarding the use of lasers to simulate gunfire in instructing pilots in aerial gunnery, the issue would not be that that lasers travel in straight lines while bullets don't, but one of speed. At the ranges typical of WWII combat bullet drop would be measured in inches, not enough to make much difference. On the other hand, in the second or two that it took for the bullets to reach the target aircraft, that aircraft could be tens of meters away. As we all know, only the select few ever really got good at compensating. 
Lasers are effectively instantaneous. You could aim one directly at an aircraft crossing g your nose ten miles away and you would hit it with no deflection at all. I can see how a fixed laser would be useful in teaching pilots how to manoeuvre into a low deflection firing position, though.
Which makes me wonder: if lasers are used to simulate gunfire in modern fighter training, how do they take deflection into account? I guess modern sighting systems would incorporate radar, so the on board computer would know the distance to the target pilot was aiming at and adjust the laser to be where the projectiles would be at that particular range. Or are modern sighting systems so good that the exercise is unnecessary and it can be taken for granted that if 
the pip on is on the target, it's gone?


----------



## J.A.W. (Mar 17, 2013)

Pilots used do a fair bit of flying target shot-gunning too, as sport/killing practice, dynamic coordination/target spotting/deflection-shot training to bag something juicy to add to the rations..


----------



## GregP (Mar 17, 2013)

I have no trouble shooting a lot of planes down in WWII simulators and no trouble in skeet / trap, either, so it's not like it would be all that different except for the bullet speed, as I said, which is rather easily learned by shootign at towed targets until you have that down. After that, it is a matter of practice and acquiring the skills to do it in aircraft versus aircraft combat.

I know people who simply cannot shoot skeet and then there are those that find it rather easy and fun. The same is probably true for pilots. Some great pilots simply can't shoot, but they have a good feel for the aircraft.

The great Aces were almost all from either rural backgrounds or aristocrary where they hunted and developed a shooting eye early in life. So it would not be surprising to learn that a good skeet / trap shooter could adapt rather easily to WWII-style fighters and sighting systems. 

But ... just my opinion.


----------

