[Rca2000]

Perhaps...a “fizzle” usually means that something “went wrong” when the bomb was detonated, and for some reason—the “secondary” did NOT fire—or fired with little yield, and the explosion was limited to the “primary” which is needed to trigger the secondary, which then, through a combination of fusion and secondary fission provides nearly all of the yield in an H-bomb....MANY times larger than the primary.

But when the secondary fails to fire properly— such as an insufficient primary burn, improper boosting, or improperly designed reflectors or such— the result is that there CAN be some “fallout” from the “unburned” fissionable components from the secondary in particular—in the small(er) explosion that the primary produces on it's own. Hopefully, the test was underground or underwater— and fallout would be contained. Had it been a “full yield” blast with a WORKING secondary...there would STILL have been some fallout and a MUCH bigger blast— at least 10 times or more—of course.

Keep in mind—at one time—the US had a 25MT bomb(B-41), that had TWO cascaded stages of secondaries—all powered by UNDER 100KT of primary power!!

[Cheetahcat]

“Perhaps...a “fizzle” usually means that something “went wrong” when the bomb was detonated, and for some reason—the “secondary” did NOT fire—or fired with little yield, and the explosion was limited to the “primary” which is needed to trigger the secondary, which then, through a combination of fusion and secondary fission provides nearly all of the yield in an H-bomb....MANY times larger than the primary.

But when the secondary fails to fire properly— such as an insufficient primary burn, improper boosting, or improperly designed reflectors or such— the result is that there CAN be some “fallout” from the “unburned” fissionable components from the secondary in particular—in the small(er) explosion that the primary produces on it's own. Hopefully, the test was underground or underwater— and fallout would be contained. Had it been a “full yield” blast with a WORKING secondary...there would STILL have been some fallout and a MUCH bigger blast— at least 10 times or more—of course.

Keep in mind—at one time—the US had a 25MT bomb(B-41), that had TWO cascaded stages of secondaries—all powered by UNDER 100KT of primary power!!”

Sir thank you for that reply it was good reading and provided insight.