WWII Anti-Aircraft Gun Questions

I’d really like to see a cite for that. Do you have any identifying information at all? Squadron/wing/service? Not even the nation is specified.

Old 666.

wiki will do:

“assigned to the 43rd bomb group in 1943, piloted by (then) capt jay zeamer (CMH). bombardier was joseph sarnoski (CMH, pstm.) it was a b-17E (early variant) with tail number 41-2666. co-pilot JT britton (DSC) said ‘take the pilot last, he’s dead.’ but zeamer wasn’t.”

correction: they were engaged by 15 zeros and 2 dinahs (k-46.) also a correction, the crew also shot down the third zero, making the crew an ace on a single mission.

IIRC you had to shoot down five planes to be an Ace. (I might be misremembering)

Also, would a whole crew become an Ace or a particular gunner? (E.g. five gunners shot down one plane each or one gunner shot down five planes…albeit all on the same bomber).

Googling “Old 666” brings up a Wiki page with a few sources:

I haven’t read it closely enough to say that it corroborates every detail in mac_bolan00’s post, but the basics seem to be right: volunteer mission, extra guns including a nose mount, highly decorated crew, etc.

I find the proximity fuze intriguing.

They were able to put a little radio transmitter, with a gadget that would compare a standing wave sent with the internal reference, and use the beat frequency generated by Doppler effects to determine when the shell was neither approaching nor retreating from the target (i.e. at the same elevation).

This was all done with tubes originally designed for hearing aids.
Part of their testing involved firing tubes from a rifle to see if they would survive.

They were such a carefully guarded secret that for much of the war proximity fuzes were authorized only for use at sea; land usage was prohibited, lest an unexploded shell provide the enemy with our secrets.

Read all about it in this excellent article:

Colley, David. “Deadly Accuracy.” Invention & Technology Magazine. Spring 2001

ETA: I saw a few folks already mentioned the key points here. I know that I hate it when people simple repeat what I have already said. At least the link to the article contributes something.

Thanks, everyone who responded

The fuses were also important in order to make sure that all shells will detonate before falling back on the ground, otherwise the AA crews would have bombed the very objectives they were trying to protect.

In fact, during the Pearl Harbor attack the japanese bombers concentrated mostly on military targets. Yet, the city itself got damaged pretty badly. It turned out latter that most of the damage was due to improper (or complete lack of) setting of fuses of AA gunnery from the american ships in the harbor. IIRC, out of 40 shells which detonated in the city, only one was japanese. Here is a short description of what happened.

I’m not sure if it’s mentioned anywhere, but if I recall correctly, the proximity fuze was found to have a nifty role in surface to surface artillery, too.

The shells were designed to explode (50ft?) a certain distance from the target. When deployed as an artillery shell, you would have a shell that bursts just over head.

Troops in slit trenches would be vulnerable to the shrapnel from above.

Height-finding was a specialised trade which some people were better at than others. Predictors (an early electro-mechanical computer) were expensive, bulky and highly specialised instruments made to analyse incoming height, distance and bearing readings and produce real-time solutions fed to the guns, both for elevation and bearing, and fuse-setting. Eventually radar and the VT fuse started to take much of the guesswork out of this - by the end of the V1 offensive in England the guns were taking a high toll of these early cruise missiles.

An interesting point about effectiveness (from the article I mentioned above):

So, 2,400 conventional-fuzed shells per aircraft compared to 400 proximity-fuzed shells per aircraft?

Both of those numbers are amazingly high IMHO. If I were to make an uneducated guess, I would have figured it took a few hundred regular shells per kill, and a dozen proximity shells would be enough to shoot down an aircraft. Clearly, my gut feel is way off.

Point of order that during the war, only Americans (and their Western allies) had proximity fuses.

My father was in the fringes of the Hurtgen Forest battle, where tree cover detonated a lot of German shells overhaed, giving the Germans something like the benefits of proximity fuses, and definitely felt that proximity fuses were deadly.

Shooting down a plane is really hard, but forcing him to fly higher/weave around and miss with his bombs is almost as good.

As said, the tight formations were for mutual protection against fighters.

As for the actual bombing run, I’m going to rely on memory (not first-hand!) so I may have some details wrong.

IIRC, the formation would fly to the Initial Point (IP), staying in formation to provide protection against fighters. Upon reaching the IP, which was miles from the target (I don’t know how many), the lead plane would turn on-target with the rest of the bombers following. The plane will be on autopilot. When the pilot has established straight-and-level unaccelerated flight, the bombardier could ‘level’ his bomb sight; i.e., calibrate it for the bombing run. The pilot would flip a switch to turn control of the autopilot over to the bombardier. The bombardier could adjust the aircraft’s flight using the autopilot controls. The bomb bay doors open, the bombardier would put the crosshairs of his bomb sight onto the target. When the crosshairs of the bomb sight reached the target crosshairs, the bombs would be automatically released. The rest of the raid would then drop their bombs. I don’t know if the other bombardiers used automatic dropping, or if the bombardiers dropped their loads manually upon seeing the lead plane drop.

I actually have a DVD of a WWII instructional film on the Norden bomb sight. I haven’t watched it yet.

On ships, you had Fire Control Stations, including for the AA guns. In their case, they would use special equipment to estimate the altitude and speed of attacking aircraft, and relay the information to the AA gunners. The shells would be fuzed to explode around where the planes should be.

Think about this: The ship(hence, the gun itself) is moving. There may be wind. The planes are moving, fast, hundreds of miles an hour, hundreds/thousands of feet in the air. The shell travels at a given speed. And through all this you are trying to hurl a shell so it will be in the same vicinity as the plane you are trying to shoot down.

On a low-tech level, the best solution is to get as many shells in the air as possible. Later, proximity fuzes helped, but for a considerable part of the naval war they had to do it the hard way.

Perfect example is the Bismark. When they were attacking the Bismark with Swordfish torpedo bombers, all the planes made it back in one piece. Biplanes! How could a huge, modern battleship miss hitting a bunch of slow-moving biplanes? Their guns were calibrated against faster moving planes. The Swordfish bombers were moving slower than the gunners predicted, so their aim was completely off.

The classic tale of this. In the Med they actually had Italian fighter planes miss-judge their attack dive run and fly into the ocean; naturally the biplane pilots claimed them as combat kills!

Here’s the MK51 AA Directorused by the Allies. Good for 40mm Bofors guns. Later versions included radar assistance.

My father’s uncle was in artillery in WWII, and they had to do it the old fashion way.

According to him, they would fire rounds with phosphor which would burn the Germans so badly that they would jump out of their trenches, and then they would fire high explosive shells.

Any truth to this?

Don’t know about the White Phosphor, but the Brits had a nasty artillery tactic in WWI. From their own experience, the British knew that men wearing gas masks would start going nuts from the irritation after an hour or so and begin ripping them off. So the Royal Artillery would fire just enough gas shells into the target zone to force the Germans to keep their masks on. Then, after an hour or so, really begin saturating the target area with gas shells to catch the guys who had removed their masks. Here’s a link to the relevant article.

Radar was important certainly but the Germans had it from the off as well.
More important was the organisation of the information gleaned from radar. The “analogue internet” of visual spotters, radar and airfield reporting was brilliantly conceived and executed. It was certainly the key factor in winning the Battle of Britain