[PA Engineer]

I have always been troubled by B.N.s, however I have had lingering doubts about the efficaciousness of them. My reservations are based on the age of the device that we are describing. If they were produced in the last couple of years I would be greatly alarmed, but from what I understand it has been quite some time since the former Soviet Union produced them for their SF arsenal. If indeed they are over 20 years of age then I would assume that the basic core decay would render these devices less effective. Can any Freepers add to this? Are these old devices? If old, how effective would they be after natural core decay?

[DBrow]

If old, how effective would they be after natural core decay?

Uranium 235 has a half-life of 71 million years and Pu239 has a half-life of 24,400 years, so an age of a few hundred years would not seriously deplete either core.

There may be other isotopes such as polonium (6 months) or tritium (about 12 years) that would limit life. If I were a weapons designer I'd design them so that they all required some depot level maintenance, to cover just such a circumstance of losing physical control of the devices. On the other hand a perverse engineering group could design them to last 50 or 100 years, just in case they had to survive a long time "underground" and several disarmament treaties.

In a world without strategic nukes for retaliation a small stockpile of little bombs would carry considerable weight.

If I remember correctly our old Davy Crockett had some limited life components.