W87

Missile warheadUnited StatesThermonuclear (staged)

No freely licensed photo of this device yet.

Yield · TNT equivalent300 kt

Key specs

Country: United States
Design: Thermonuclear (staged)
Type: Missile warhead
Weight: 200 kg
Length: 1.75 m
Diameter: 550 mm
In service: 1986 – present
Number built: 525

Overview

A 300 kt warhead in the Mk 21 re-entry vehicle, built for the LGM-118 Peacekeeper and moved to the Minuteman III after Peacekeeper was retired. A new 475 kt W87-1 is planned to replace the W78.

Effect radii: estimates

Calculated for 300 kt

Fireball, maximum radius: ≈ 600 m
Initial radiation, 500 rem (5 Sv): ≈ 2.5 km
Blast 5 psi: most buildings collapse: ≈ 4.8 km
Thermal: third-degree burns: ≈ 6.9 km
Blast 1 psi: windows shatter: ≈ 15 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

Complete List of All U.S. Nuclear Weapons, Nuclear Weapon Archive (Carey Sublette)
W87, Wikipedia