There is a hydrogen bomb on the Atlantic ocean floor

In 1958, a 3,400-kg (7,600-pound) hydrogen bomb was lost in the Atlantic ocean. It was carried by a US B-47 bomber when it collided in midair with an F-86 fighter plane. Despite being damaged, the B-47 remained airborne and purposefully jettisoned the bomb into the water to reduce the aircraft weight and prevent the bomb exploding during the emergency landing.

Read more. http://todayilearned.co.uk/2011/08/13/t ... ean-floor/

Maybe. I think Captain Nemo has taken it to use at a later date.

I wonder if the Defense Department did try to retrieve it and never admitted to getting it back.

VL can Pretty much free dive for it.