B17 B24 Defensive weapons

How effective were the .50 caliber machine guns, the turrent and waist gunners? Would they have been better off carrying more fuel and bombs?

German pilots were loathe to attack these aircraft.

I think it’s wrong to say any single gun was or was not effective. These were huge formations bristling with literally hundreds of weapons. It’s not correct to try to evaluate the effectiveness of a single gunner.

Also, keep in mind that at the beginning of the war, the fighter escorts did not have enough fuel to keep pace with the bomber formation. Those guns were the only defense the bombers had. They still suffered a disturbingly high casualty rate, but without those guns they would have been utterly defenseless.

“Fips” Phillips, a 200+ Eastern Front Ace wrote the following while in command of JG 1 defending against American Bombers over Northern Germany:

From here: http://freepages.military.rootsweb.ancestry.com/~josephkennedy/German_Pilot_Perspective.htm

Lots of other good info on that page, such as the “point” system that pilots were awarded (1 point for downing a single engine fighter, 3 points for a B-17, 2 points just for damaging a B-17 to the point where it has to break formation).

Another quote from that page:

The defensive screen a bomber formation could put up could put the fear into the heats of the Luftwaffle. I remember one story by a B 17 to turret Gunner. He recounted a mission where the formation was being attacked by ME262s (jets). He said one made a run and then flew or ahead of the formation to get into position to attack had in. When he began his attack every gun that could be brought to bear on him was. He said that 262 literally disappeared in a bright flash as it hit a wallfof lead.

They weren’t necessarily all that effective in the sense of destroying vast numbers of Luftwaffe fighters. Many bombers never shot down any fighters. Others got a couple over their lifetime.

But their defenses were the only thing that let any bomber survive their first mission. Or their second. Or their third. …

As said above, for much of the air war over Germany there were no allied fighters with the range to provide escort.

So the effect was more like a porcupine. The porc’s quills kill very few wolves. But they keep a lot of porcupines alive nonetheless.

It’s also important to understand that a bomber in formation was protected by all the surrounding bombers. Any bomber that got separated from the flock was pretty much screwed. If any fighter with enough fuel & ammo found them alone, they were dead. So one bomber generally could not hold off one fighter. But 20 bombers could (mostly) hold off 20 fighters.

And remember that head-on was the weak spot in most bombers.

How were the guns set up so the gunners couldn’t shoot their own aircraft? Obviously the tail and nose gunners didn’t have to worry about it, but the top turret and waist gunners could have shot their own wings and tail. Did the guns have some kind of physical stop to prevent gunners from shooting themselves down?

They would have been worse off with less guns, because as it turned out they couldn’t do the job they were built for alone without entailing huge losses.

Originally The Army Air Force believed that heavy bombers bristling with defensive machine guns (namely the B-17) could adequately defend themselves from attacking fighters and complete their bombing missions with acceptable losses. But they were incorrect. Percentage-wise their losses were the USA’s worst in all of WWII. Something around 40% of the crews flying the European bombing missions died. That’s higher than even the Marines’ losses fighting the Japanese in the pacific. If it wasn’t for the introduction of the long-range P-51 Mustang to protect the bombers the whole way those losses would have been unsustainable.

The British never accepted that un-escorted, precision daylight bombing would work, hence they only pursued night-time area bombing.

The Luftwaffe employed a number of strategies to break up the formations, including using unguided rockets fired by fighters as well as building an armored version of the FW 190 which could take greater punishment.

By the end of 1943, the Germans were winning the contest, and by the time the second Schweinfurt raid occurred, the US lost almost 30% of the bombers. It was unsustainable and they had to stop bombing for months to rebuild their forces. It wasn’t until they had the P-51 that they could resume day raids.

That said, without that many guns they simply could have never lasted so long.

Here is very detailedanalysis of defensive armament..

As it says

In Tanks and Bombers American farm boys died in droves. The American reply was that they had plenty more farm boys.

As did the Americans; in the Pacific.

According to the freepages link above, which I can’t vouch for. The rockets and armour degraded their performance to the point where they needed to be escorted by 109’s for protection from the Mustangs.

Did the rockets have some proximity or time fuze? A plane trying to hit another plane with a rocket seems like quite a challenge.
Also, I take it that the use of 20mm and 30mm cannons on fighters was intended to allow the fighters to shoot bombers while staying out of range of their defensive guns?

Yes, but also due to the fact it was quickly realized that the normal 7.92mm or even 13 mm machine guns mounted on their aircraft weren’t sufficient against heavily armed bombers. In fact certain American fighters such as the P-47 could shrug off hundreds of rounds of 7.92mm, while a 30mm cannon was able to destroy a bomber in just a few hits.

It helps that their targets were all paper and wood buildings. Gets a nice firestorm brewing.

The rockets were impact fused. The key innovation is they were fired in volleys which spread out due to natural variations in how each flew. So it was sort of an aerial shotgun versus trying to snipe at the other aircraft with a rifle.

The other difference is the rockets were big and visible. It was much harder to hold formation while watching large one-hit=one-kill weapons coming at you than it was seeing fighters swarming but not knowing who they’re after.

The very short range of the defensive .50cal machine guns meant the bombers had to fly very close together to obtain mutual protection. So close that collision was a constant concern. Once spread out they may have been navigating as a group, but they were defending as individuals. And didn’t stand a chance, individually or collectively, against fighters.

Once a formation got disorganized enough, it was impractical to get back together. Somebody believes a rocket’s going to hit, so they pull up or down or left or whatever to evade, somebody else evades them, and suddenly you’ve got aerial bumper cars. As soon as the formation is loosened the conventional fighters with machineguns are all over it.

The rockets didn’t kill that many bombers directly. But it disrupted their defense something fierce. Which then allowed the kill.
Conceptually similar disruptive tactics are used today against enemy ground attack aircraft groupings and against enemy air-to-air fighter sweeps.
As to cannon, the gain was 2x-3x range and 10-30x lethality per shot. The cost was carrying only about 10-20% as much ammo. They rewarded marksmanship & patience more than balls & bravado.

I thought that the problem with ME-262s attacking B-17s was running out of fuel.
They made high speed runs through formations until they were out of gas.

Like many things in combat, its not always the hard kill, getting holed by a dozen .50cal round can break things that rendered a fighter non combat effective or unable to continue. Leaking fuel/fluids, control surfaces damaged or inoperable, pilot injured, etc. Such outcomes were probably far more common than actual kills but would represent a huge boost to the perceived threat of defensive gunnery by German pilots.

Back to the OP.

There was a fast British bomber called the Mosquito than when it was in the bomber role had few weapons and could fly faster than anything the Germans had.

Funny that they brought back volley fire.

Ah, like wolves/lions sowing panic in a herd to scatter and isolate individuals.
Did the USAF have you studying air tactics back to WWI or is it your personal interest?

I can’t be the only one curious about those.