Editing Nuclear weapon design (section)

===Hollow-pit implosion===
{{Unreferenced section|date=October 2022}}
A more efficient implosion system uses a hollow pit.{{Citation needed|date=June 2021}}

A hollow plutonium pit was the original plan for the 1945 Fat Man bomb, but there was not enough time to develop and test the implosion system for it. A simpler solid-pit design was considered more reliable, given the time constraints, but it required a heavy U-238 tamper, a thick aluminium pusher, and three tons of high explosives.{{Citation needed|date=June 2021}}

After the war, interest in the hollow pit design was revived. Its obvious advantage is that a hollow shell of plutonium, shock-deformed and driven inward toward its empty center, would carry momentum into its violent assembly as a solid sphere. It would be self-tamping, requiring a smaller U-238 tamper, no aluminium pusher, and less high explosive.{{Citation needed|date=June 2021}}