Mark 13 nuclear bomb

TheMark 13 nuclear bomband its variant, theW-13 nuclear warheadfor Redstone BM and Snark CM, were experimentalnuclear weaponsdeveloped by the United States from 1951 to 1954. The Mark 13 design was based on the earlierMark 6 nuclear bombdesign, which was in turn based on theMark 4 nuclear bomband theMark 3 nuclear bombused at the end ofWorld War II.

Description

The Mark 13 bomb was nearly the same size as theMark 6 nuclear bombit was developed from; 61 inches in diameter and 128 inches long (150 cm by 320 cm), weighing 7,400 lb (3,300 kg). The W-13 warhead was somewhat smaller, being roughly 58 inches in diameter and 100 inches long, with a 6,000 to 6,500 lb weight (145 cm by 250 cm, 2,700 kg to 2,900 kg).

The Mark 13 design used a 92-point nuclear implosion system (seeNuclear weapon design). A similar 92-point system was used in later variants of the Mark 6 weapon.

Testing

The Mark 13 nuclear bomb design was tested at least once, in theOperation Upshot–KnotholeHarrytest shot conducted on May 19, 1953. The estimated yield of this test was 32kilotons.

Deployment

As the Mark 13 neared production, advances inthermonuclear weapon design,particularly theIvy Mikethermonuclear test in November 1952, made the Mark 13 obsolete. Development continued for research purposes (the Upshot-Knothole Harry test shot came months after the first thermonuclear test in Ivy Mike), and in two variant designs, but the Mark 13 proper was never deployed. The Mark 13 bomb version was cancelled in August 1953, and the W-13warheadversion was cancelled in September 1953.

Variants

Mark 18

TheMark 18 nuclear bombalso known as theSuper Oralloy Bomb(or its initialsSOB) utilized the 92-point Mark 13 implosion system, but a differentfissile corewith around 60 kilograms ofhighly enriched uranium(Oralloy). This was the largest pure fission nuclear bomb ever tested, with a yield of more than 500 kilotons. The Mark 18 was produced in moderate quantities (90 units) and in service from 1953 to 1956.

Mark 20

TheMark 20 nuclear bombwas a planned successor to the Mark 13 incorporating some improvements in its design. Research was halted at the same time as the Mark 13.

The Mark 20 was the same size as the Mark 13, but weighed only 6,400 lb (2,900 kg).

See also

• List of nuclear weapons
• Mark 18 nuclear bomb
• Mark 6 nuclear bomb
• Mark 4 nuclear bomb
• Fat Man Mark 3 nuclear bomb