B-47s did fly with actual Nuclear Weapons.
Usually safely, but not always.
Like the time a B-47 dropped a Nuclear Bomb on South Carolina.
They had just taken off from Hunter AFB, near Savannah were headed for England.
Then the Weapons Panel indicated an unsafe condition.
So the Navigator Bruce Kulka went into the bomb bay to insert the safety pin in the bomb suspension jaws.
He reached for support and grabbed the naked EBL wire, Emergency Bomb Release. The bomb jaws opened and the weapon fell through the closed Bomb Bay doors.
Now Bruce is hanging on the side of the bomb bay which has no floor!
Luckily nobody on the ground was killed and the Pilot safely landed the B-47.
Yes, the EBL wire was modified and enclosed.
Bruce? Later he was in B-58s, then in SEA he was in Ranch Hand, Agent Orange.
1958 Mars Bluff B-47 nuclear weapon loss incident - Wikipedia