Yellow Sun

Aircraft bombUnited KingdomThermonuclear (staged)

No freely licensed photo of this device yet.

Yield · TNT equivalent0.4–1.1 Mt

Key specs

Country: United Kingdom
Design: Thermonuclear (staged)
Type: Aircraft bomb
Weight: 3.29 t
Length: 6.4 m
Diameter: 1.22 m
In service: 1959–1972

Overview

Britain’s first operational high-yield bomb, carried by the Vulcan and Victor V-bombers. The Mk 1 used the 400 kt Green Grass fission warhead; the Mk 2 from 1961 used the Red Snow thermonuclear warhead of about 1.1 Mt, derived from the American W28.

Effect radii: estimates

Calculated for 1.1 Mt

Fireball, maximum radius: ≈ 1 km
Initial radiation, 500 rem (5 Sv): ≈ 3.2 km
Blast 5 psi: most buildings collapse: ≈ 7.3 km
Thermal: third-degree burns: ≈ 12 km
Blast 1 psi: windows shatter: ≈ 23 km

Estimated ground ranges for an air burst at the optimum height over flat, open ground, computed from the yield with standard scaling laws. These are not measurements: real effects depend on the height of burst, terrain, buildings and weather.

Formulas from: Glasstone & Dolan, The Effects of Nuclear Weapons (1977), chapter II; Carey Sublette, Nuclear Weapons FAQ, section 5

Sources

Yellow Sun (nuclear weapon), Wikipedia