→ 2 He + n + 15.123 MeV This resultant extra fuel (both lithium-6 and lithium-7) contributed greatly to the fusion reactions and neutron production and in this manner greatly increased the device's explosive output. The test used lithium with a high percentage of lithium-7 only because lithium-6 was then scarce and expensive; the later Castle Union test used almost pure lithium-6. Had sufficient lithium-6 been available, the usability of the common lithium-7 might not have been discovered. The unexpectedly high yield of the device severely damaged many of the permanent buildings on the control site island on the far side of the atoll. Little of the desired diagnostic data on the shot was collected; many instruments designed to transmit their data back before being destroyed by the blast were instead vaporized instantly, while most of the instruments that were expected to be recovered for data retrieval were destroyed by the blast. In an additional unexpected event, albeit one of far less consequence, X-rays traveling through line-of-sight (LOS) pipes caused a small second fireball at Station 1200 with a yield of . High levels of fallout The fission reactions of the natural uranium tamper were quite dirty, producing a large amount of fallout. That, combined with the larger than expected yield and a major wind shift, produced some very serious consequences for those in the fallout range. In the declassified film Operation Castle, the task force commander Major General Percy Clarkson pointed to a diagram indicating that the wind shift was still in the range of "acceptable fallout", although just barely. The decision to carry out the Bravo test under the prevailing winds was made by Dr. Alvin C. Graves, the Scientific Director of Operation Castle. Graves had total authority over detonating the weapon, above that of the military commander of Operation Castle. Graves appears in the widely available film of the earlier 1952 test "Ivy Mike", which examines the last-minute fallout decisions. The narrator, the western actor Reed Hadley, is filmed aboard the control ship in that film, showing the final conference. Hadley points out that 20,000 people live in the potential area of the fallout. He asks the control panel scientist if the test can be aborted and is told "yes", but it would ruin all their preparations in setting up timed measuring instruments. In Mike, the fallout correctly landed north of the inhabited area but, in the