RDS-1

Aircraft bombSoviet UnionImplosion fission

Yield · TNT equivalent22 kt

Key specs

Country: Soviet Union
Design: Implosion fission
Type: Aircraft bomb
Weight: 4.7 t
Length: 3.3 m
Diameter: 1.5 m
In service: 1949

Overview

The first Soviet atomic bomb, tested on 29 August 1949 at Semipalatinsk with a yield of 22 kt. A plutonium implosion design closely modelled on Fat Man, it ended the American nuclear monopoly four years after Hiroshima.

The project was led by Igor Kurchatov, with Yulii Khariton in charge of the bomb itself, and drew on intelligence from the Manhattan Project. The device was fired on a tower; US aircraft detected the fallout, and President Truman announced the test on 23 September 1949. A small series was built for the stockpile from 1949 to 1951.

Effect radii: estimates

Calculated for 22 kt

Fireball, maximum radius: ≈ 210 m
Initial radiation, 500 rem (5 Sv): ≈ 1.5 km
Blast 5 psi: most buildings collapse: ≈ 2 km
Thermal: third-degree burns: ≈ 2.4 km
Blast 1 psi: windows shatter: ≈ 6.2 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

Tests and use

Date	Event	Site	Yield
Aug 29, 1949	First Lightning (Joe-1)Tower shot; the first Soviet nuclear test.	Semipalatinsk Test Site, Kazakh SSR	22 kt

Test footage

Archive films hosted on YouTube. Nothing loads from YouTube until you press play; the player then comes from youtube-nocookie.com.

atomcentral · youtube.com

Sources

Soviet Nuclear Test Summary, Nuclear Weapon Archive (Carey Sublette)
RDS-1, Wikipedia
РДС-1, Википедия