Just out of curiosity, could the Fuhrerbunker take a 15 KT hit?
Enola Gay dropped Little Boy, around 240 meters from the aiming point, the Aioi Bridge, so pretty good accuracy from over 30,000 feet
The Fuhrerbunkers lowest level was 8.5 meters deep, so likely the crater would have missed, and just outside to 200psi blast effect radius.
But would have gotten between 500 and 1000 rem, plus since this was a surface burst, unlike OTL, there would be fallout,
From NUKEMAP
Effects radii for 15 kiloton surface burst (smallest to largest): ▼
Crater inside radius: 50 m (0.01 km²)
↓
Crater depth: 20 m Crater lip radius: 100 m (0.03 km²)
Air blast radius (200 psi): 200 m (0.12 km²)
200 psi is approximately the pressure felt inside of a steam boiler on a locomotive. Extreme damage to all civilian structures, some damage to even "hardened" structures.
Fireball radius: 230 m (0.17 km²)
Maximum size of the nuclear fireball; relevance to lived effects depends on height of detonation. If it touches the ground, the amount of radioactive fallout is significantly increased.
Air blast radius (20 psi): 0.54 km (0.9 km²)
At 20 psi overpressure, heavily built concrete buildings are severely damaged or demolished; fatalities approach 100%. Often used as a standard benchmark for
heavy damage in cities.
Thermal radiation radius (35 cal/cm2): 0.86 km (2.32 km²)
Air blast radius (5 psi): 1.13 km (4 km²)
At 5 psi overpressure, most residential buildings collapse, injuries are universal, fatalities are widespread. Often used as a standard benchmark for
medium damage in cities.
Radiation radius (1000 rem): 1.21 km (4.56 km²)
1000 rem radiation dose; with immediate medical treatment, 95% mortality can be expected. Dying takes between several hours and several weeks.
Radiation radius (500 rem): 1.34 km (5.64 km²)
500 rem radiation dose; without medical treatment, there can be expected between 50% and 90% mortality from acute effects alone. Dying takes between several hours and several weeks.
Thermal radiation radius (3rd degree burns): 1.68 km (8.92 km²)
Third degree burns extend throughout the layers of skin, and are often painless because they destroy the pain nerves. They can cause severe scarring or disablement, and can require amputation. 100% probability for 3rd degree burns at this yield is 8.7 cal/cm2.