Kinglet was a boosted fission primary used in several Americanthermonuclear weapons.[1]
The W55 warhead for theUUM-44 SUBROC anti-submarine missile and theW58 warhead forPolaris A-3 were designed to use Kinglet, while theW47 warhead for Polaris A-1/A-2 were retrofitted with Kinglet to overcome the technical issues with theRobin primary the W47 was initially deployed with.[2][3] Allegedly, only the W47Y2[a] was converted to the Mod 3 design using Kinglet.[4]
The Kinglet device was approximately 11.2–11.57 inches (284–294 mm) in diameter, 11.5–12.2 inches (290–310 mm) in length and weighed approximately 58–63 pounds (26–29 kg).[5]
The device was of the two-point design. Two-point devices only require two detonators to fire the whole device, compared to earlier nuclear weapons that required tens of detonators.[6]
Characteristics of the warheads that used Kinglet are:[5][7][8]
| Warhead | Max Yield | Diameter | Length | Weight |
|---|---|---|---|---|
| W47Y2 Mod 3[4] | 1,200 kilotonnes of TNT (5,000 TJ) | 457 mm (18 in) | 1,194 mm (47 in) | 332 kg (733 lb) |
| W55 | 5 kilotonnes of TNT (21 TJ)[b] | 343 mm (13.5 in) | 1,001 mm (39.4 in) | 213 kg (470 lb) |
| W58 | 200 kilotonnes of TNT (840 TJ) | 396 mm (15.6 in) | 1,016 mm (40 in) | 117 kg (257 lb) |