Even one loss of a nuclear-armed aircraft is a disaster. That B-52 that crashed in Palomares Spain is still causing problems 50 years later.
747s are an overaged, weak aircraft. Criminally stupid idea.
C-17s would be a better choice.
I would assume the designers had a reason for picking the 747, maybe because it’s faster, bigger (about 50 feet longer) and can fly almost 5000 nm further.
Not sure what you mean about ‘overaged’.
Old design or just old?
The 747 is still in production, although they’re talking about winding it down. So it would be a new plane.
As far as old design, I would imagine that they would plan on starting with a stripped airframe anyway.