Jughead was replaced in the Yankee test by the so-called "Runt II" device (the TX-24 bomb, initially the "emergency capability" EC-24), a modified form of the "Runt" device (the TX-17/EC-17) tested in Castle Romeo. Externally identical, the principal difference between them was in the fuel for the fusion stage. While Runt used natural lithium (with 7.5% of the Lithium-6 isotope), Runt II used the same partially enriched lithium (approximately 40% Lithium-6) as the "Shrimp" device tested in Bravo.
It was detonated on May 5, 1954, at Bikini Atoll of the Marshall Islands, on a barge moored in the middle of the crater from the Castle Union test.
Although it had been predicted to produce a yield of 6 to 10 megatons, it actually produced a yield of 13.5 megatons, the second-largest ever yield in a U.S. fusion weapon test. Like the Ivy Mike, Bravo and Romeo tests, a large percentage of the yield was produced by fast fission of the natural uranium "tamper"; 7 megatons of the yield was from this source. The other 6.5 megatons were from fusion reactions; (this increase was due to the different fusion fuel)....
It was detonated on May 5, 1954, at Bikini Atoll of the Marshall Islands, on a barge moored in the middle of the crater from the Castle Union test.
Although it had been predicted to produce a yield of 6 to 10 megatons, it actually produced a yield of 13.5 megatons, the second-largest ever yield in a U.S. fusion weapon test. Like the Ivy Mike, Bravo and Romeo tests, a large percentage of the yield was produced by fast fission of the natural uranium "tamper"; 7 megatons of the yield was from this source. The other 6.5 megatons were from fusion reactions; (this increase was due to the different fusion fuel)....
