B-17 - FLYING FORTRESS?

[spaddad]

Now that Airfix have released their B -17 I thought the time might be right to bring something to everyones attention that has bothered me for years in order to see what others think. I have been modelling for 50 years give or take and absorbing any and all information on the aircraft I model but never have I ever seen this point raised or even mentioned by anybody.

My point is this, we all know a B-17 or B-24 carried 13 or 10 machine guns for defence, sounds good doesn't it. But it was only when I analysed things in a bit more detail that my respect for the crews of these planes, which was already very high went through the roof.

Let me explain. The usual ammo load for an operational B-17 was 6380 rounds,or roughly 500 rpg, I haven't been able to ascertain the load out for the B-24 but 500 or 600rpg seems a reasonable assumption. The standard model of the M2 mounted in the bombers was the AN/M2 which had a rate of fire of 750-850 rounds/min giving a total firing time of approximately 30 to 45 seconds per gun, lets call it a minute.  A MINUTE,  these guys were getting on their plane knowing they had a mission involving a flight time of 4 to 8 HOURS over enemy territory with enough ammo for 1 MINUTES combat, that's balls of steel with a capital ST! Has anybody else thought about this, has everybody else thought about this and I've just been extremely dim and slow on the uptake.
What I find even more unbelievable is the callous way the American bomber advocate generals could order their men out time after time just to prove their theories knowing this.

Anyway just wanted to say very brave men.

[e8n2]

2 hours ago, spaddad said:

What I find even more unbelievable is the callous way the American bomber advocate generals could order their men out time after time just to prove their theories knowing this.

Anyway just wanted to say very brave men.

I doubt very much that the top echelon, of for example, 8th Bomber Command, thought they were callously throwing away lives just to prove a far fetched theory.  They wanted to prove theories promoted by many airpower advocates, and not just American, that the bomber could always get through.  Experience was a hard teacher and they adjusted tactics, to include forming bomber boxes for mutual defense, and having escorts follow them as far as the escorts could based on their range capabilities at the time.  It really wasn't until the P-51B came on line and they started adding drop tanks to the P-47s to extend range that the fighters were able to escort them all the to and from the target.  Remember also that the escorts acted in relays, so there never was one fighter unit escorting the same bomber unit all the way to and from the target.  One fighter group would take them part way, another would hook up further on down the line, and so on until they were back over "Blighty".  It might help to watch the movie "Twelve O'clock High" and see how things were for those in command.  The book upon which the movie was based was written by someone who flew those missions and knew of what he spoke.  The RAF's nocturnal missions were no piece of cake either and they really didn't have a lot of escorts until later in the war.  "Bomber" Harris has often been labeled as a callous leader, but I would imagine the losses incurred took a hard toll on him as well.  Simply put, you do the best with what you have and make adjustments as necessary.

Later,

Dave

[Work In Progress]

 

One minute of combat is not one minute of continuous gun firing. What you have at your disposal is 90 half-second bursts. Which is quite a lot, if you only fire (as you should) on the very few occasions when you have the gun accurately sighted leading a viable target within effective range and with no friendly aircraft liable to be caught in the crossfire (itself quite rare given the USAAF's application of close box formations). Each of those bursts throws a dozen .50 bullets at an enemy fighter and is more than enough to destroy it.

 

Hollywood's completely unrealistic depictions of combat have much to answer for in this respect. If you fire a machine gun in real life the way people do in movies the barrel will melt off after about a minute and the heat built up would make it completely inaccurate within ten seconds. This is why air gunners were thoroughly trained, not Hollywood cowboys.

 

As a point of comparison, how much ammunition do you think a typical paratrooper of the 101st Airborne had on him when landing on D-Day? A lot less than a B-17 gunner.

 

3 hours ago, spaddad said:

What I find even more unbelievable is the callous way the American bomber advocate generals could order their men out time after time just to prove their theories knowing this.WW

 

That's not why they sent those men out: it is a gross misrepresentation of their motives. Their intention was directly to degrade German industrial capacity, and to force the Germans to devote so many military resources (especially air power and 88mm guns and their crews) to home defence that their ability to fight on the Russian front and (post D-Day) against the advancing British and American forces in Europe was severely reduced.

Edited November 5, 2016 by Work In Progress

[Procopius]

4 minutes ago, Work In Progress said:

Each of those bursts throws a dozen .50 bullets at an enemy fighter and is more than enough to destroy it.

 

A dozen fifty-caliber bullets enough to destroy a Fw190? Is Annie Oakely behind the gun?

[Work In Progress]

If you hit it, yes, it is, More than enough. .50 BMG is not .303 confetti. 12 rounds of BMG will take out a Buick, never mind something as comparitively flimsy as an aluminium fighter aeroplane full of fuel.

 

If you miss it, then the damage is zero no matter how many many you fire.

 

Of course a lot of them did miss, or couldn't get clear shots, but that's combat. Daylight gunners trained for box formation were very differently trained, and behaved very differently, from night gunners in loose streams RAF bombers. Night gunners were mainly using tracers to try to scare people off, and fought their one aircraft in isolation from any others. Day gunners were trying to kill fighters as a multi-aircraft team, a wing box of 50+  defensive aircraft in close formation, and did a pretty good job under the circumstances. Which is why the Luftwaffe had to resort to things like head-on attacks.

 

Incidentally, coming back to the rounds-per-gun thing: the P-51D used to fly all the way there and all the way back with 400 rounds per gun for the inboard two guns, 270 rounds each for the outer four guns.  A lot fewer rounds per gun than the B-17s carried. Enemy fighters weren't towing ammo trucks around the sky either.

Edited November 5, 2016 by Work In Progress

[Procopius]

7 minutes ago, Work In Progress said:

If you hit it, yes, it is, More than enough. .50 BMG is not .303 confetti. 12 rounds of BMG will take out a Buick, never mind something as comparitively flimsy as an aluminium fighter aeroplane full of fuel.

 

I would be very curious to see documentation showing the downing of Luftwaffe fighters between 1942-45 with only twelve or fewer hits from 0.50 caliber ammunition as anything more than incredible luck or incredible skill on the part of the shooter. It was considered exceptional shooting when "Mike" Crosley brought down a Fw190 with 20 rounds per gun of 20mm cannon ammunition at 150 yards range on D+1 in 1944 with "many hits". 

[Shane]

3 hours ago, spaddad said:

 The standard model of the M2 mounted in the bombers was the AN/M2 which had a rate of fire of 750-850 rounds/min giving a total firing time of approximately 30 to 45 seconds per gun, lets call it a minute.  A MINUTE,  these guys were getting on their plane knowing they had a mission involving a flight time of 4 to 8 HOURS over enemy territory with enough ammo for 1 MINUTES combat, that's balls of steel with a capital ST! Has anybody else thought about this, has everybody else thought about this and I've just been extremely dim and slow on the uptake.

 

AH, but. Hollywood notwithstanding, MGs are NOT fired continuously for anything like a minute.

 

Many a long year ago my employer gave me the pleasure to carry a 23lb+ M-60 GPMG wherever I went, with at least one spare 100 round belt worn bandolier style. My number two, and the section 2ic carried another four hundred or so rounds between them. Lets say a total of 600-800 rounds for a gun firing ~600rpm.  That's just over one minute too, but no-one fires 100 round bursts, and in the fleeting opportunities in air combat I bet it's rare as well.

 

Shane

[Work In Progress]

30 minutes ago, Procopius said:

 

I would be very curious to see documentation showing the downing of Luftwaffe fighters between 1942-45 with only twelve or fewer hits from 0.50 caliber ammunition as anything more than incredible luck or incredible skill on the part of the shooter. It was considered exceptional shooting when "Mike" Crosley brought down a Fw190 with 20 rounds per gun of 20mm cannon ammunition at 150 yards range on D+1 in 1944 with "many hits". 

 

There can by definition be no such documentation as you well know, because no-one dug up the wrecks of FW-190s shot down by B-17 gunners and counted the bullet holes, and none of them had camera gun evidence. However, you're missing the point that I am addressing. I'm talking about what the gunners were trained to attempt, not what they actually achieved in practice. Of course almost every bullet and every shell fired in war misses. I'm not claiming that the average gunner brought down a fighter every time he fired a half-second burst, any more than the FW-190 pilots hit their targets every time they opened fire. I'm saying that the daytime box-formation aerial gunner was trained to fire bursts which were military effective, and that therefore the original suggestion that 400RPG was some sort of wanton under-equipment of the daylight bomber force is incorrect to the point of absurdity.

 

That militarily effective way to use the .50 gun in that context was roughly a half second burst, and 400 rounds of ammo per gun in no way resembles the assertion of "enough ammo for 1 MINUTES combat".

 

But, if you want to talk damage, then yes, if you can actually get 12 rounds of BMG  into a 109 or 190, there is a good chance of that being a kill. As with heavy bullets hitting people, the exit wound for each of those .50 hits, depending on what it hit while inside the airframe, could be far more significant than the entry wound. And if not a kill then it would at the very least make him go away. Even if he did make it back to base but is wounded then the pilot is out of action for a while, or permanently. And even if he is unwounded the aircraft is either a write-off or out of action for a significant period of time, which for the purposes of round the clock bombing campaigns is very nearly as good.

 

 

Edited November 5, 2016 by Work In Progress

[MilneBay]

It is one of the big debating points of WW2 - the success and cost of the US daylight bombing offensive. It grew from the very simple problem that until radar came along no one could see their target unless it was in plain sight. The defensive tactics and deployment grew from that. USAAF losses were very high and was becoming prohibitive by mid to late 1943.

 

The deployment of long range fighters able to fly with the bombers to the target and back began in early 1944 solved that problem but not even they were a match for the German AA which was the real killer - the Luftwaffe despite the large claims of some pilots was not a huge deterrent once the USAAF fighters came into action and even then both would avoid the heavy flak killing grounds over the targets.

 

The problem for the Germans was that they really only got one pass at the bomber formations as did the defensive gunners get one chance at the attacking fighters. Such was the speed of combat flying that by the time a Luftwaffe fighter had made its firing run whether successful or not it also was low on ammunition and likely to become a target for both the escort fighters and ironically German flak which was an indiscriminate killer of both sides. Ammunition loads for bomber defenses were calculated around these few seconds of contact. And then it was based not on pin point accuracy but providing a brief moment in which many gunners unleashed very short bursts at an incoming attacker. The overall thinking was that out of all the gunners firing someone had to hit the target rather than relying on one eagle-eyed champion shot.

[Denford]

Not often mentioned is that 60% of all German Day Fighters were deployed to the defence/defense of the Reich.

When the Invasion came, even though as expected somewhere along the channel coast and during the summer months, ONLY TWO AIRCRAFT, were immediately available!   This vital contribution of the daylight bombing campaign is invariably overlooked.

 

And spare a thought for the Luftwaffe pilots too.  More and more outnumbered as the war progressed, there was no such thing as a Tour.  You flew on till you were killed or permanently incapacitated.  As if that wasn't enough, there was the added humiliation of your commander, Göring, calling you cowards to cover up his failings as a commander.  Truly brave men.

[Graham Boak]

I suggest that you read a little bit further into the "only 2 aircraft on D-Day" - this is one of those Good Stories.  Before Priller's much recorded mission there had already been combat between night-operating Fw190s and the Lancasters laying the radar screen.  There were two Jagdgeschwader on the Western front at the time of D-Day, as there had been since Operation Barbarossa, well before the US Bomber Offensive.  Many other units were prepared to be deployed one the invasion occurred, as indeed did happen (regardless of the US bombers).

[Jure Miljevic]

Hi!

The main reason behind bomber's defensive armament was to keep fighters at distance thus making their aim inaccurate and hits less likely. Hitting Luftwaffe fighters, inexperience or reckless enough to fly into gunner's range, and rendering them hors de combat, was secondary. If those two task had been fulfilled, gunners' work was done and bombers could proceed toward their targets (relatively) unmolested. Destroying Luftwaffe fighters and killing their pilots was just a bonus, although a very welcome one. Unless their bomber had been forced out of formation, 500 RPG was plenty. By the way, ammunition had not been distributed evenly, tail gunners always had had plenty of it.

From German perspective, defence against high flying mass daylight raids started as a difficult task, which by late 1944 gradually turned into mission impossible. Consider this: it was difficult enough to catch Allied bombers, cruising at 20000 ft. and development that went into high altitude fighters and gadgets like MW50, MW30, GM-1 and others to improve their engines attest to that. Then it was a question of armament. Regular Bf 109 versions, quite effective against fighters, were too lightly armed to pose a serious threat against bombers, unless they closed in and expose themselves to very effective bomber formation defensive fire. Fw 190 armament had been more suitable, but radial engine versions lacked power at altitude. Adding extra guns, rockets and similar increased punch of fighter's armament, but degraded their performance and such overweight fighters were highly unpopular among Luftwaffe pilots. If Offenrohr (21-cm rocket) armed Bf 109s met Allied fighters, it was standard procedure to fire their rockets into the blue, as otherwise fighters could shed their wings in maneuvers like split-S. Armament of heavy twins like Bf 110 or Me 410 was adequate, but losses if caught by bomber's escort were by early 1944 prohibitive. Cheers

Jure

P.S.: I vaguely remember reading some time ago about Ju 88 bombing raids at dusk on D-Day and possibly also about Do 217 sorties.

[bobmig]

I suggest a good introduction to what this aerial combat was like for the bomber crew is to watch "The Memphis Belle". Not the ridiculous Hollywood film, but the original 40 minute wartime documentary. Sure it's wartime propaganda, but at least it was filmed 'live and on location', as they say. (Some interesting colour and markings info too!)

Bob

 

[Denford]

From fighters to flack.

The bombers really had little answer but to tough it out.  Only as the fighter threat diminished were the formations 'reconfigured' to make them a slightly less vulnerable target.

The drain on the German war effort to provide anti aircraft fire must have been both immense and frustrating.  Immobile, idle for much of the time, yet essential to have in place.  If only they could have been released, say, for the eastern front.... 

Here too is another bomber contribution (albeit rather indirect) to the war effort, allowing Churchill to tell Stalin that a second front had already been opened.

Putting so much effort into defence plus the ongoing repair of damage is no way to win a war.

[old thumper]

I am not an expert but seem to remember that ammunition loads were tailored to suit each mission, as were fuel loads and bomb loads.

Within RAF Mitchell squadrons not all gun positions were being manned by wars end, this was due to provision of fighter escorts and lack of fighter opposition.  

 

Going back to the point of whether enough ammunition was carried by USAAF heavy bombers.

Maybe a way of finding the answer to this question would be to discover how much unused ammunition was brought home. I would expect a lot more ammunition was typically expended in 1943 than in 1945.

[Potato Pete]

In John Comer's Combat Crew, he recalls unofficially topping up with extra ammunition for at least one mission - so you could bypass the official load if you knew the right people.

 

He also recalls that the extra ammunition was stowed in the tail of the plane, upsetting it's centre of gravity and almost causing it to fail to become airborne.

 

[Procopius]

11 hours ago, Work In Progress said:

 

There can by definition be no such documentation as you well know, because no-one dug up the wrecks of FW-190s shot down by B-17 gunners and counted the bullet holes, and none of them had camera gun evidence.

 

 

However, plenty of Allied fighters did. Twelve bullets would be exactly 2 rpg from a Mustang hitting a Fw190 or Bf109 in the zone of conversion. Think about how ludicrous that sounds for a second. I don't dispute that with luck, twelve, or even one 0.50 bullet could bring down an aircraft, any aircraft, but to imply as you do that the probable result of twelve bullets hitting a fighter from a machinegun would bring it down strikes me as impossible to countenance. 

[Ratch]

But it wasn't necessarily just one gun doing the damage.

[Jure Miljevic]

Hi!

Attacking bomber formation was a risky business. Most bombers, shot down by fighters, flew in exposed positions at the fringes of bomber box, where the attacker met with a defensive fire of the least number of guns. Why do you think attacking single bombers or small groups of two or three was so popular among Luftwaffe fighter pilots? And why do you think in internal Luftwaffe counting Herausabschuss (forcing bomber out of formation) counted for more than Vernichtung (finishing-off straggler)? Cheers

Jure

[Ascoteer]

13 hours ago, Procopius said:

A dozen fifty-caliber bullets enough to destroy a Fw190? Is Annie Oakely behind the gun?

 

The .50 cal firing API (Armour Piercing Incendiary) was almost a cannon.

 

You'd only need a handful of strikes to knock a fighter down.

 

May I suggest you read Lt Col Richard E Turner's seminal work 'Mustang Pilot'? He rather well describes what API would do to an Me109 of FW190.

 

 

I've seen 50 cal in action - it will chop a brick built house down in no time squared.

[occa]

3 hours ago, bobmig said:

I suggest a good introduction to what this aerial combat was like for the bomber crew is to watch "The Memphis Belle". Not the ridiculous Hollywood film, but the original 40 minute wartime documentary. Sure it's wartime propaganda, but at least it was filmed 'live and on location', as they say. (Some interesting colour and markings info too!)

Bob

 

 

Extremely interesting camoflage scheme at 1:30, never noticed such before

[Pete in Lincs]

I've seen the grey and green before.

I have an idea it was an option on

a Monogram? kit years ago.

[woody37]

I would if thought one luckily placed bullet of any size can bring down a fighter, jams or snaps a control cable and it's out of the game. 

[Garry c]

Don't forget about the "Akutan Zero" brought down by one bullet which severed the oil return line.

 

Garry c

[occa]

This one seems to consist of three colours, at least on the rudder:

 

 

 

Here's a different AC with a similar pattern