1935-45: alternative airborne weapons

[Gunnarnz]

Ships at sea would also produce a strong radar return. This system could be used for attacking even the largest enemy warship. Even the Yamato would not have survived Tallboy or Grand slam hits. It wouldn't take many. And if it had been attacked at night from 30,000 feet they might not have even know they were being attacked meaning no evasive maneuvering. However if this system works even a maneuvering ship would still be hit.

A Tallboy or Grand Slam would certainly make a big hole, but I'm not sure if it would be as dangerous as the sheer weight might suggest. These bombs did their damage by penetrating beneath their target and then creating a huge cavern, which collapsed and caused the target to "fall in" to the camouflet created.

I know Tallboys were used for attacking Tirpitz, so presumably they were thought effective against floating targets. I also know that modern torpedoes kill ships by creating a huge bubble under the keel, which tends to cause ships to break in half. Would Tallboys or Grand Slams create a similar effect? If not, and if a kill would be the result of kinetic energy on impact and explosive effects inside the target, Tallboys would seem to be entirely adequate for the job.

One proviso: Tallboys and Grand Slams had their fins canted, so they rotated as they fell to improve accuracy. Would this rotation interfere with the control method suggested here?

 

[Driftless]

I know Tallboys were used for attacking Tirpitz, so presumably they were thought effective against floating targets. I also know that modern torpedoes kill ships by creating a huge bubble under the keel, which tends to cause ships to break in half. Would Tallboys or Grand Slams create a similar effect? If not, and if a kill would be the result of kinetic energy on impact and explosive effects inside the target, Tallboys would seem to be entirely adequate for the job.

When the Tirpitz was finally destroyed, I think it was moored in comparatively shallow water, (The capsized hull bottom shows clearly above the water level in photos).

Some direct hits did the critical damage. Had they been near misses in that shallow water, might you also get hull ruptures from horizontal shockwaves, as well as the bubble effect?

From Wikipedia:

 

[Carl Schwamberger]

I don't recall any mention of very long range fighters here. Its correct types like the Me110 were VLR by the standards of 1938, or the P38 in 1941. But what about airframe, engine, fuel, configurations to get the range of a P51 circa 1939? If not that then with twin engined airframes?

On a simpler level is there any practical reason to exclude drop tanks by 1938?

 

[Gunnarnz]

On a simpler level is there any practical reason to exclude drop tanks by 1938?

I don't see any mechanical reason they shouldn't have been possible, even much earlier than that. One potential issue is logistic - early drop tanks were made of aluminium ISTR, and supplying large numbers of those would be a noticeable expense to a peace-time air force. Later drop tanks were made of papier-mache, so getting there quickly would be a good step. There might also be doctrinal issues: short-range fighters defending against bombers don't really need them, and bombers are big enough that they can carry the fuel internally, so they don't need the fuel either. You'd need some perceived need driving the use of drop tanks, and VLR fighters aren't an obvious necessity before it becomes apparent that the bomber, in fact, will not always get through.

 

[Canuck Wingnut]

On a simpler level is there any practical reason to exclude drop tanks by 1938?

There was some use of drop tanks and similar concepts prewar, so the reasons they didn't receive widespread adoption were financial and doctrinal, not technological.

My personal favorite of the prewar drop tank proposals was the slip-wing, trialed during the war on a modified Hawker Hurricane (referred to as the Hillman F.H. 40). The concept was that the fuel tank would also be an upper wing, turning the Hurricane into a biplane with greater lift for takeoff and the initial climb to altitude, before being dropped. Some prewar proposals suggested the entire thing should be a glider with its own pilot!

If an interwar aircraft equipped to carry such a device were adopted for service, I suspect that the hardpoints for attaching the slip wing would prove irresistible for armament developers. Whether rockets or some kind of gun pod, I can't imagine an aircraft with hardpoints designed to handle that kind of weight and already plumbed into some kind of control system (to allow the pilot to jettison the rig) wouldn't end up used to enhance firepower by somebody.

I wonder how effective a bomb could be developed for the Hurricane in the shape of an upper wing? If you could design it to rotate once dropped, like a maple key, it could make one hell of a submunitions dispenser.

Also, now I kind of want to see a war movie where a squad of apparent biplanes bravely flying into battle against superior odds suddenly all drop their upper wings in unison and reveal themselves as modern monoplanes.

 

[CaptainCalvert]

I don't see any mechanical reason they shouldn't have been possible, even much earlier than that. One potential issue is logistic - early drop tanks were made of aluminium ISTR, and supplying large numbers of those would be a noticeable expense to a peace-time air force. Later drop tanks were made of papier-mache, so getting there quickly would be a good step. There might also be doctrinal issues: short-range fighters defending against bombers don't really need them, and bombers are big enough that they can carry the fuel internally, so they don't need the fuel either. You'd need some perceived need driving the use of drop tanks, and VLR fighters aren't an obvious necessity before it becomes apparent that the bomber, in fact, will not always get through.

One argument in favour of drop tanks is that it extends loiter time of aircraft designed as interceptors, so that either you can hang around CAP-style in case something shows, or form up a big wing. Otherwise use fuel to get into fighting position without affecting time in combat. In all cases the drop tank would be ditched prior to actual combat (even better if over enemy bomber formation at the time). Though now I think of it, that is an argument against use over friendly territory.
Edit. Carl Schwamberger's sycamore-wing bomb sounds like a near-perfect incendiary dispenser.

 

[marathag]

Could these and similar heavy weight bombs have been dropped using radar guidance?

The USN 'BAT' worked with radar as the sea had less Ground Clutter to return spurious signals.

For the era, TV Guidance is your best bet, as troublesome as it would be

XBQ and TDR Drones/UAV used TV guidance, and the TDR actually saw very limited combat

 

[marathag]

t's the high explosive 30 mm shell that is the hidden gem here.

Could the Allies have developed a similar weapon?

The Madsen 23mm had a very early type of 'Mine' shell, and this was before the War started

 

[CaptainCalvert]

The Madsen 23mm had a very early type of 'Mine' shell, and this was before the War started
View attachment 738225

Madsen seemed to produce some good weapons.

 

[sonofpegasus]

The Madsen suffered from a low ROF and being magazine fed.
However the 23mm ammunition would IMHO have been very effective in the early years of WW2

 

[CaptainCalvert]

The Madsens look good on paper!

 

[Millsy]

Always liked the idea in PAM I think of the 'cluster bomb' with either 2" or 3" mortar bombs as the munitions - good for softer targets and anti airfield bomb and run attacks

 

[CaptainCalvert]

I wonder if a 37/40mm cannon could fire a modern equivalent of chain shot as a defensive tail gunner weapon. I'm thinking two weighted ends with a long length of fine steel wire and maybe some ribbon to slow descent a bit. The idea is you fire a couple of these and they tangle the propellor, snag on the wing etc. I'd imagine they'd be about as effective as an airborne flamethrower, but it would sound good right up until it was tested.

 

[ArtosStark]

The UK also used the .50 Vickers (link) but this was another fairly mediocre design, despite beating the Browning M1924 in trials (there seems to have been some bias).

No bias, the Vickers .5 Inch was compared against the M1924 Browning .50 Caliber. The improved M2 only came around in the 30's. And though the Vickers was chosen (more reliable and simpler) for the RN, the RAF actually found not much to choose between them. The Browning was more powerful but heavier and larger. They thus decided not to use a heavy machine gun at the time, with the idea to change policy if armour started to be added to aircraft. When aircraft became more robust, they decided to go for a 20 mm instead.

 

[tomo pauk]

The Madsen suffered from a low ROF and being magazine fed.
However the 23mm ammunition would IMHO have been very effective in the early years of WW2

Madsen's 23mm round is as similar to the Soviet/Russian 23mmx115 as possible. The later round is still used today, introduced just past the ww2.
For the Luftwaffe, a cannon firing the Madsen's 23mm it would've made a lot of sense in any day of ww2. Talk one-two-three on Bf 109, 2-4 on a Fw 190, 4 on Me 262, two on an 1-engined jet figther, 4-6 on night fighters...

I wonder if a 37/40mm cannon could fire a modern equivalent of chain shot as a defensive tail gunner weapon. I'm thinking two weighted ends with a long length of fine steel wire and maybe some ribbon to slow descent a bit. The idea is you fire a couple of these and they tangle the propellor, snag on the wing etc. I'd imagine they'd be about as effective as an airborne flamethrower, but it would sound good right up until it was tested.

A time-fused 37-40mm shell for a defensive cannon? Timed for a 300-400m explosion; two of those plus one 'ordinary' round in the belt?
A 'shotgun' 37-40mm ammo perhaps?

 

[marathag]

The Madsen suffered from a low ROF and being magazine fed.

The 23mm and 20mm it was based on, were belt fed.
Somewhere I have pics from a 1940ish USAAC photo of the flex-mount Madsen used in trial install on a bomber waist gun position. If I can track it down, will post.
They weren't exactly a drop-in replacement for 50 Browning, but close

 

[marathag]

I wonder if a 37/40mm cannon could fire a modern equivalent of chain shot as a defensive tail gunner weapon. I'm thinking two weighted ends with a long length of fine steel wire and maybe some ribbon to slow descent a bit. The idea is you fire a couple of these and they tangle the propellor, snag on the wing etc. I'd imagine they'd be about as effective as an airborne flamethrower, but it would sound good right up until it was tested.

Hmm. A helical setup for a expanding rod payload in a time fuzed cannon shell, with that being the shell wall.
You get one or two long pieces of shrapnel, rather than the chunks, fragments and near dust of a regular HE casing.

 

[Draconis]

One proviso: Tallboys and Grand Slams had their fins canted, so they rotated as they fell to improve accuracy. Would this rotation interfere with the control method suggested here?

Yes, it would confuse the operator as to which directional control to apply to steer the bomb if it was rotating. However I don't see why these bombs would still need to be built with canted fins to spin stabilize them for accuracy when they are fitted with the radar guided RAZON control system.

 

[Draconis]

I don't know about other nations, but the US Army Air Corps did buy a batch of something like that in the 1920s. I'd have to search for the details. According to Gambles 'Fortress Rabaul' Gen Kenny requested and got for his 5th AF in 1942 a large part of those which were still in storage in the US.

Are you referring to the parachute bombs aka parafrags? General Kenney, who invented them, had the supply all shipped to New Guinea for the 5th Air Force to use. They provided an effect similar to cluster bombs. I'll provide a link to an article about them.

The Pacific War Online Encyclopedia: Parafrag Bombs

pwencycl.kgbudge.com

U.S. Air Force. Via Truman Library

"The parafrag bomb was invented by Kenney in the 1920s and put to good use in the Southwest Pacific. It was a relatively small bomb (24 pounds or 11 kilograms) scored to break into 1" (25mm) fragments on detonation and equipped with a small parachute. The parachute allowed the bomb to be dropped directly over the target in a low-level attack while allowing the attacking aircraft to get clear before detonation. The low weight allowed a very large number of these weapons to be dropped at once. The effect of a parafrag attack was to saturate a zone half a mile long with bomb fragments. Kenney was able to have 23-pound fragmentation bombs shipped in quantity to the Southwest Pacific, mostly because they weren't wanted anywhere else, and his ground crews then attached the parachutes.

The parafrag bomb was thus an ancestor of both modern laydown bombs and of cluster ammunition. It was highly effective against airfields, since its fragments shredded aluminum airframes and its delivery in large numbers from directly above foiled ordinary aircraft revetments.

The parafrag was standardized by March 1945 as the AN-M40. A finned version for use from altitude was standardized as the AN-M41, while a cluster of 25 AN-M41 bombs was standardized as the M26.

The Japanese copied the idea after examining dud American parafrag bombs, but to little effect. The Japanese parafrags were much lighter (about 8 pounds or 3.6 kilograms) and were equipped with an arming propeller that often malfunctioned, resulting in a high dud rate." From the Pacific War Online Encyclopedia.

 

[CaptainCalvert]

Hmm. A helical setup for a expanding rod payload in a time fuzed cannon shell, with that being the shell wall.
You get one or two long pieces of shrapnel, rather than the chunks, fragments and near dust of a regular HE casing.

I agree it's not going to work well (if it works at all), but it only needs one enthusiastic type to have visions of props tangled in wires to start things off.