Would Hitler in his bunker have survived a 1945 atomic bomb dropped on Berlin?
Most likely, yes. The bombs dropped on Hiroshima na Nagasaki were all “air burst” detonations-the bombs were timed to go off while at about 2000’ altitude.
In Hiroshima, the downtaown bank vaults are survived.
The “fuhrerbunker” was built of reinforced concrete, and was 555’ under the streets.
Hitler would have survived. But I don’t know about getting out-were there multiple exits?
As I recall, the Soviet troops did not find the bunker till several weeks after they took Berlin.
I agree he would’ve survived, but it wasn’t nearly that deep, and yes, there were multiple exits: Führerbunker - Wikipedia
See the 2004 movie Downfall starring Bruno Ganz for a fascinating look at Hitler’s last days.
The only thing I might guess could get him was the radioactive dust in the air. The bunker was not sealed, though it probably did have some protections against poison gas attack.
If the allies were aiming to take out the bunker, they probably would not do a high-level air burst, I assume.
So they let of a 3 to 10 kiloton blast at about ground level, plus or minus a few hundred feet. If it was pretty close to the bunker, then even if the roof survived the blast without collapsing, I presume it would do in any exit routes long enough for occupants to suffocate.
So the loical follow-up questions have to do with the accuracy of allied intelligence about the precise location of Hitler’s bunker; the accuracy of bombing and the effective delivery systems.
the Enola Gay was not bothered because it was a solo aircraft. What I’ve read said the Japanese assumed it was a photo-reconnaisance flight, since all previous bomber raids involved large fleets of bombers. I guess they thought a solo bomber not intent on doing damage was not worth the aircraft to respond. (Or they didn’t have enough to waste against the bomber’s guns for a simple target).
How likely that a small fleet of aircraft could fly over Berlin undisturbed? How many companion aircraft would you send to ensure the single very very expensive bomb made it there unmolested? (I’d hate to be bailing out of an aircraft that was going to turn into the world’s biggest fireball when it hit the ground below me…)
As a side note, did FDR/Truman or Churchill have a similar bunker that they could use if they ever needed it?
Did the Japanese Emperor have a similar bunker in Tokyo?
The fact that Hitler built the bunker meant that he realized that things might not turn out as well as he had hoped. I had always assumed that ***he ***had assumed that he would win the war.
Wouldn’t keeping out radioactive dust be easier than keeping out gas, so that a system capable of the latter would necessarily suffice to accomplish the former? 
FDR did:
I haven’t found the details, but presumably Churchill had something along those lines (especially seeing as how London, unlike Washington, actually did get bombed).
I suspect he stands quite a good chance of surviving the initial explosion, but almost certainly dies in the firestorm.
As usual, it all depends on what assumptions are made about the circumstances. The Allies could guess that some bunker existed, but they did not know the exact location. Usually they didn’t even know whether Hitler was in Berlin at any particular time. But, in the absence of better intelligence, a decapitation strike on the city would surely have aimed for the New Reich Chancellery. Even if he isn’t in town, all the main government ministries are clustered around the Wilhelmstrasse. The bunker is in the back garden of your aim point.
Airburst or are you going to detonate it at rooftop height? In this instance, I suspect the latter, but we can speculate on the results of either choice.
Accuracy. This is the big unknown. Tibbets and his crew were close at Hiroshima, Sweeney and his were way, way out at Nagasaki. The accuracy stats for regular bombing crews over Germany are well known. So we could be anywhere from a few yards to a few miles out. In the latter case, he survives.
Now consider the case of Eizo Nomura. He happened to be in the basement of a building when Hiroshima was bombed and only about 150 metres from the hypocentre. (It’s an airburst, so he’s somewhat further from the actual bomb itself.) He suffered serious burns and blast injuries, but essentially walked away. Furthermore, he reported that 8 other colleagues in the same building survived the initial explosion, though some in much worse condition. He left them to seek help and it appears they died in the firestorm. Nomura made it out. (He died about 10 years later, relatively young and I suspect of radiation-related illness.)
The bunker was a substantially better protected structure than the basement he was in. Some, perhaps all, of those in it would have survived a similar airburst, no matter how well targeted. What happens then is their serious problem.
What about a ground burst? The Trinity test depressed the desert floor by about 6 feet. So I suspect there’s a good chance a “direct hit” would serious compromise the structural integrity of the bunker. Otherwise, the dangers mainly follow from you being much closer to the explosion. The radiation danger is much higher, but there’s a lot of concrete in between. Temperatures outside are significantly higher and I suspect it’s that that will indirectly kill the occupants - they’re going to find themselves without any air very, very quickly.
Less accurately placed ground bursts quickly become like airbursts, at least as far as those in the bunker are concerned. Fallout is, of course, much nastier.
Someone on Hitler’s staff must have wondered what would happen to him were the Allies able to start a firestorm in Berlin, but I suspect the plan was just to try to get him out as fast as possible. Exactly the plan that would break down under a surprise nuclear attack on the city.
On Churchill, the Cabinet War Rooms were designed to take anything short of a direct conventional hit. Quite an achievement secretly building a substantial concrete ceiling underneath one of the major government buildings in London.
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Germans are notoriously thorough that way. Having a plan B is nothing to them. They often don’t start complaining until you ask them for, like, plan F.
During the Cold War, here in Canada we had Emergency Government Headquarters, also known as “Diefenbunkers,” named for John Diefenbaker, Prime Minster at the time they were built. One of the communication bunkers was located at Canadian Forces Base North Bay, about half an hour from me.
In Japan, the Matsushiro Underground Imperial Headquarters was intended to be a safe spot for the Emperor. Never finished, etc. Well away from Tokyo. The Imperial family waited out bombings in their own bomb shelters, the Imperial residence was never targeted and only tangentially damaged.
The Russians did enter the Berlin bunker as they fought their ways thru the chancellery. No delay at all. They found it abandoned (though Stalin’s PR claimed a heroic battle of course). They didn’t know it existed.
If the Russians didn’t know about it, there was no way anyone could have planned a successful A-bomb attack on Hitler’s HQ at that time.
I’m pretty sure the Soviets found the bunker almost as soon as they reached the Chancellery.
that’s because it’s actually Plan S in Fraktur.
Yes FDR had one I even seem to remember a few years ago one of the presidents bomb shelters was unclassified after it was no longer to be used. It was just set up in an ordinary shop or something like a pizzicato and in the back you go through all these secret doors and end up far underground
I suspect it also depends WHICH bomb you drop on him - Fat Man or Little Boy. It’s worth noting that distances from the hypocenter that were survivable with protection at Hiroshima were not at Nagasaki, due to the more powerful bomb. There are a few cases of close-in survival at Hiroshima; those of both Eizo Nomura, and Akiko Takakura, who was not very much further away but sheltered in a reinforced-concrete bank building, are well known. There are almost no such cases at the same distance in Nagasaki. Hiroshima had a firestorm, and still had a few reinforced concrete buildings still standing quite close to the hypocenter; Nagasaki didn’t.
Actually, it’s almost impossible to find any information about the ‘closest survivors’ at Nagasaki at all. I don’t trust Pellegrino’s accounts of such in “Last Train” because his history is so bad in other areas and with other survivor stories - it’s pretty clear he’s just making a lot of stuff up. But that’s a whole 'nother issue.
If the Allies knew the exact location of the bunker and wanted to destroy it they would have used one of these, a Grand Slamearthquake bomb.
Well that presume super accuracy. Had we know the exact location we could have sent a swarm of Mosquitos going in high while B-17s flew a diversionary raide below. Say thirty Grand Slam variants striking within 2km of the aimpoint within say two minutes. This would have a good chance of a fatal strike, and would almost certainly collapse at least one exit.
Then what? Hitler is spirited away to get his fillings tightened and his shorts cleaned then to some location outside the city. Dresden or Potsdam come to mind.
Why don’t you gentleman have a Pepsi?