I’d guess the reason they didn’t go the Castle Bravo route is probably just that it’s hard to work deep in the arctic, where you as the USSR can test with minimal (but not zero, RIP Severny) impact. There was also the official justification that the extremely clean burn was the point of the test, which would be defeated by contact with and activation of the ground. It seems SHRIMP from Castle Bravo weighed 10 tonnes, so picture adding a nose and tailfins and maybe some electronics to it and you’d still have a more practical weapon.
Here’s the aerodynamic casing for the Tsar Bomba (empty, which is how it can sit on that dolly):
See, you say “undeliverable” and I picture Castle Bravo, which was the size and shape of a microbrewery.
I’d guess the reason they didn’t go the Castle Bravo route is probably just that it’s hard to work deep in the arctic, where you as the USSR can test with minimal (but not zero, RIP Severny) impact. There was also the official justification that the extremely clean burn was the point of the test, which would be defeated by contact with and activation of the ground. It seems SHRIMP from Castle Bravo weighed 10 tonnes, so picture adding a nose and tailfins and maybe some electronics to it and you’d still have a more practical weapon.
Here’s the aerodynamic casing for the Tsar Bomba (empty, which is how it can sit on that dolly):