WI: US Nuclear Weapons Operational One Year Earlier

[marathag]

Technically speaking, though, you could do it in a Skyraider and survive, if you've got a light (in mass) enough bomb. I think I've tried it myself in a flight sim a coupla times, years back, and got some encouraging distance numbers.

OTL They would use the toss bombing technique to gain more time to escape the area

The Algorithm of Armageddon
The Low Altitude Bombing System was devised at Dayton's Wright Field in 1952. The following spring, LABS-equipped F-84G Thunderjets were deployed to Europe and the Pacific. In time, the technique was adopted by the U.S. Navy, the British, and of course the Russians. Pilots loved it. They called it the Goofy Loop, competing in annual loft-bombing games at Nellis AFB in Nevada.
The constant-G pullup was key, so the loop's radius remained unchanged from the start of the pullup until the bomb released. Writing in Air University Quarterly Review in 1957, shortly after the technique was made public, Colonel John A. Ryan Jr. gave this example of the calculations involved:

A Thunderjet pilot approached his target at 880 feet per second (520 knots), 50 feet off the deck, and began a 4-G pullup. His loop had a radius of 8,000 feet. The bomb was programmed to release when the Thunderjet pointed 40 degrees off the horizontal, separating from the underwing pylon at 1,920 feet above the ground. By this time, the Thunderjet's speed was 809 feet per second (478 knots).

Following gravity's rainbow, the nuke kept climbing, reaching the top of its arc 16.1 seconds later, at an altitude of 4,240 feet. Then it fell, reaching burst altitude 31.4 seconds after parting company from the Thunderjet. Meanwhile, it traveled 22,000 feet horizontally--a bit more than four miles from the release point.

"The flight path of the aircraft is somewhat more complicated to calculate," Colonel Ryan conceded. "The aircraft would be at the top of the [loop] the same time as the bomb reaches its summit and during the remaining 19 or so seconds to burst would be accelerating outbound from the target, placing the aircraft some 35 to 40 thousand feet from the burst." Call it seven miles. In theory, this was sufficient for the Thunderjet to escape a 100 kiloton burst.

A variant called "over-the-shoulder" was used against targets that had no easily-identified IP, or if a straight-away escape was desired. Here, the pilot threw the nuke backwards, after he passed the vertical but before he reached top of the loop. He then completed the loop and pulled out at blast level without changing direction. Over-the-shoulder was easier to perform, but it provided less separation from the blast.

Lofting remains a feasible way to deliver bombs (British Harriers used the technique to attack Stanley airport during the Falklands War) but has passed out of favor for nuclear weapons. In the 1960s, parachute-retarded nukes came into the inventory, giving a turbojet time to escape without acrobatics.
https://www.warbirdforum.com/toss.htm

 

[Download]

It took years for the USAF to get the drogue and parachute deployment right for multi-ton bombs.

Citation needed.

 

[marathag]

Citation needed.

Why goto the effort of putting in another black box for calculating the proper toss bomb technique in '52 if they could have just put a parachute on the bomb?
There wasn't a working drogue setup for heavy bombs until 1954.

High speed release would shred typical WWII design parachute for the size of chutes needed, so the drogue chute was developed to slow the bomb, all while not changing the course of the weapon.
Kevlar was was eventually used, nylon wasn't strong enough for high drag chutes

 

[viperjock]

Everyone is concentrating on Germany but let's take a break and look at Japan.
would atomic bombs be enough to make the Japanese surrender? If the 20th Air Force begins it's bombing campaign against Japan from Saipan with nuclear bombings will Japan call it quits right away?

 

[sloreck]

The problem with starting B-29 operations with atomic weapons from the Marianas in late 1944 is that the USA does not have Iwo Jima. Having Iwo both eliminates some Japanese early warning as well as providing an emergency landing strip. OTL the first emergency landing there was even before island was completely secured. Of course having Okinawa is even better. Also in late 1944 Japanese home defense from a fighter standpoint is not as crushed as it would be the next August. Given the problems the B-29 had, and silverplates were not immune from this, a mission from the Marianas in late 1944 has a lot of risks even if the Japanese don't shoot them down.

Assuming that the US does drop a bomb on Japan. I expect that the Japanese would look at where they are - US forces and forces in SEA are atill away from the core and also seized areas. I expect that once the Japanese twig to what a B-29 can do, you'll have Kamikazes crashing in to B-29s every time they appear. Also in late fall 1944 Japanese cities have barely been touched by strategic bombing, the atomic bomb was icing on a large cake of destruction.

I am not one who says that Russia piling on in August 1944 (between Hirsohima and Nagasaki) was the deciding factor. For sure as loing as the USSR is fighting Germany in fall, 1944 they are NOT going to be attacking Japan. The agreement they had with the USA was coming in 90 days after Germany surrendered, and frankly while still trying to crush Germany the Soviets can't do anything to help. In fact if they do join the war in the Pacific, then the lend-lease that was shipped on Soviet freighters fro the US across the Pacific goes away.

 

[MattII]

They could do it and survive, but it would probably have to use a Lancaster/Mosquito Mistel setup.

 

[Download]

Why goto the effort of putting in another black box for calculating the proper toss bomb technique in '52 if they could have just put a parachute on the bomb?
There wasn't a working drogue setup for heavy bombs until 1954.

High speed release would shred typical WWII design parachute for the size of chutes needed, so the drogue chute was developed to slow the bomb, all while not changing the course of the weapon.
Kevlar was was eventually used, nylon wasn't strong enough for high drag chutes

Because what toss bombing is used for completely different target approaches than parachute retarding.

It was initially developed for delivering multi-megaton weapons at low altitude. They didn't have parachute retarded weapons until 1954 because they didn't have thermonuclear weapons until then. Aircraft of the era were fast enough to escape the largest of fission weapons of the era meaning there was no need for them.

You're also very wrong to claim nylon can't be used. Early weapons did use nylon. Kevlar wasn't even invented until 1965. There is nothing to suggest engineers of the era could not design an extra-strength parachute for weapons delivery. Claiming "typical" parachutes of the era couldn't handle it is irrelevant.

 

[marathag]

They could do it and survive, but it would probably have to use a Lancaster/Mosquito Mistel setup.

Mistels were released relatively close to the target in a shallow dives.
with an A-Bomb in the belly, you would still need to be too close to the blast to ensure a decent CEP

 

[marathag]

Because what toss bombing is used for completely different target approaches than parachute retarding.

It was initially developed for delivering multi-megaton weapons at low altitude. They didn't have parachute retarded weapons until 1954 because they didn't have thermonuclear weapons until then. Aircraft of the era were fast enough to escape the largest of fission weapons of the era meaning there was no need for them.

You're also very wrong to claim nylon can't be used. Early weapons did use nylon. Kevlar wasn't even invented until 1965. There is nothing to suggest engineers of the era could not design an extra-strength parachute for weapons delivery. Claiming "typical" parachutes of the era couldn't handle it is irrelevant.

The ribbon chutes had to wait for kevlar.

But the physical size of a nylon chute would still rule out its use on the smaller Mk7, used by the Skyraiders and F-84 Leadsleds for the toss bombing profile.

Trust me, if parachutes would have worked, you would have seen them before the deployed H-Bombs, because even the improved 80kt FatMan types made escape problematic for the early Atom bombers

 

[Download]

The ribbon chutes had to wait for kevlar.

Irrelevant.

But the physical size of a nylon chute would still rule out its use on the smaller Mk7, used by the Skyraiders and F-84 Leadsleds for the toss bombing profile.

You've just answered your own question as to why smaller weapons didn't have them. We're not here designing small weapons for small tactical aircraft.

Trust me,

No.

if parachutes would have worked, you would have seen them before the deployed H-Bombs, because even the improved 80kt FatMan types made escape problematic for the early Atom bombers

Citation needed.

Freefall was a fuzing option on the B53 bomb. If a B52 can survive that drop, an aircraft with 2/3rds the altitude and half the speed can survive a weapon with 1/100th the yield.

 

[marathag]

Freefall was a fuzing option on the B53 bomb. If a B52 can survive that drop, an aircraft with 2/3rds the altitude and half the speed can survive a weapon with 1/100th the yield.

B-52 flew faster and higher than a Skyraider.

Like I said, they would have used parachutes for tactical delivery in the early '50s if it was possible. But had to do toss bombing instead.

Since you are so sure of yourself, prove me wrong.

 

[Download]

B-52 flew faster and higher than a Skyraider.

Like I said, they would have used parachutes for tactical delivery in the early '50s if it was possible. But had to do toss bombing instead.

Since you are so sure of yourself, prove me wrong.

You've already explained yourself why toss bombing was used; small weapons, small delivery aircraft. This is on top of the fact it's more accurate than parachutes, and the fact you don't need to fly over the target to deliver the weapon, and they allow you to deliver weapons at only a few thousand feet and still use airburst fuzing.

All of which means squat to delivering bombs because we're not discussing the Skyraider delivering weapons at 2000ft, we're discussing delivery by a WW2 heavy bomber at very high altitude.

 

[Simon]

Couldn't they use a parachute?

Alternatively something like the later British Yellow Sun nuclear bomb casing which was designed with a blunted nose to induce drag and slow it's fall, as well as avoiding shock wave problems.

 

[Cryhavoc101]

Strip down a Lancaster - remove the Turrets etc and stream line it.

Should be good for a 15-20 kiloton weapon

 

[Catsmate]

Using tons of handwavium, the US is able to produce nuclear weapons one year earlier than IOTL. The first nuclear test is conducted in July 1944, and first bombs are available for operational use in early August. Against which targets they will be used and how the final phase of war will generally unfold?

1. What is the production rate compared to the historical?
2. What is the delivery platform?
3. Has this impacted other WAllied military production? Are there fewer landing craft, escorts, artillery shells, bombers, machine guns et cetera.

ETA.
4. Did Overlord go ahead as planned?

 

[Catsmate]

OK, but now you have to also handwave silverplate B-29s being available for this mission as well, there may be need to extend a runway in England and of course build the bomb pit. In August 1944 the Luftwaffe is not impotent, so there is the issue of tactics. You could have some B-29s start flying over Germany singly or flights of 3 to get the Germans acclimated to "recon" flights which they may decide not to try and intercept given the small numbers and altitudes. Of course this may spur them to work on getting high to intercept them if their radar finds then. I expect the safest thing would be to do this at night, the B-29s have decent bomb radar to find a city, you could even send a pathfinder ahead with a short interval, and with an A-bomb, aiming at the center of the city is all you need.

No matter what getting the bomb delivered over any German city in August, 1944 is going to be tricky as while the odds of the Germans being able to do anything with a captured [partially wrecked A-bomb are small, simply seeing how little fissile material is needed would be a huge bump for them. Heisenberg was gobsmacked when he realized his calculations on needed material were totally wrong.

This.

Prior to OTL use of the bombs on Japan, I don't think anyone appreciated just how dangerous fallout and residual radiation was (Op Downfall considered using them on defenders). So, perhaps Eisenhower would not have seen this as a concern?

Yep, Downfall planned extensive tactical and operational use of nuclear weapons, up to thirty bombs.

Couldn't they use a parachute?

That's actually quite tricky. Though given the knowledge that it would be needed, and hence the time for experimentation, probably.

A parachute bomb over a major Germany city? that's just asking for it to be shot up.

Hence the armoured casing.

 

[Catsmate]

Bombs' effect on the D-Day is a rather interesting point which I didn't consider myself. Are you suggesting that the Allies would delay the D-Day and opt for some sort of "nuclear strategy" to force Germans to surrender or wait until they have bombs to be used to support the operation?

My view is possibly delay Overlord, though risking Soviet antagonism, but not cancel it. Instead coordinate a nuclear strike, of one to three bombs if possible at daily intervals, in conjunction with the landings.

 

[Catsmate]

Not 617 Squadron, who assuredly would have been dropping it due to being the most accurate high altitude bombers ever to that point. Towards the end of the war, they were accurate within as little as 10 meters from 20K feet.

I rather doubt the USAF would have agreed with that.

 

[MattII]

Hence the armoured casing.

That was over Japan, over Germany I'm going to say that you're going to need even more.

 

[Catsmate]

That was over Japan, over Germany I'm going to say that you're going to need even more.

No really, shell fragments are shell fragments.