Lorenzo von Matterhorn
- Jan 31, 2009
- Reaction score
Magnetic Drum Digital Differential AnalyzerThis film is a gem. When I was a child, in the days of Jetex models, the Snark was my favorite missile.
As for the top secret guidance system, it's pretty clear how it worked. The part that is still befuddling
is how it worked without computers!
Cool! (Gotta plow though all that...)Magnetic Drum Digital Differential Analyzer
Development on the project began in March 1946 at Northrop Corporation with the goal of producing a subsonic cruise missile designated "MX-775," which came to be called the Snark. Northrop's parameters for this project were to create a guidance system that would allow a missile to hit a target at a distance of up to 5,000 miles with a precision that would be 200 yards better than the German "vengeance" weapons V1 and V2. Ultimately, however, the MADIDDA was never used in weaponry, and Northrop used a different analog computer as the guidance system for the Snark missile.
The jet propelled 20.5 meter-long Snark missile had a top speed of about 650 mph (1,046 km/h) and a maximum range of about 5,500 nautical miles (10,200 kilometers). Its complicated celestial navigation system gave it a claimed CEP of about 8,000 feet (2.4 kilometers).
Mark 39 nuclear bomb
The Mark 39 design was a thermonuclear bomb (see Teller-Ulam design) and had a yield of 3.8 megatons. The design is an improved Mark 15 nuclear bomb design (the TX-15-X3 design and Mark 39 Mod 0 were the same design). The Mark 15 was the first lightweight US thermonuclear bomb.
The W39 warhead is 35 inches (89 cm) in diameter and 106 inches (270 cm) long, with a weight of 6,230-pound (2,830 kg) to 6,400-pound (2,900 kg). It was used on the SM-62 Snark missile, Redstone IRBM missile, and in the B-58 Hustler weapons pod.
So, a 3.8 megaton bomb detonating as much as 2.4 kilometers away from the aim point:
Effects radii for 3.8 megaton optimum height airburst (smallest to largest):
Fireball radius: 1.65 km (8.53 km²)
Maximum size of the nuclear fireball; relevance to lived effects depends on height of detonation. If it touches the ground, the amount of radioactive fallout is significantly increased. Minimum burst height for negligible fallout: 1.48 km.
Radiation radius (500 rem): 2.94 km (27.2 km²)
500 rem radiation dose; without medical treatment, there can be expected between 50% and 90% mortality from acute effects alone. Dying takes between several hours and several weeks.
Air blast radius (20 psi): 4.4 km (60.9 km²)
At 20 psi overpressure, heavily built concrete buildings are severely damaged or demolished; fatalities approach 100%. Optimal height of burst to maximize this effect is 2.84 km.
Air blast radius (5 psi): 10.9 km (371 km²)
At 5 psi overpressure, most residential buildings collapse, injuries are universal, fatalities are widespread. Optimal height of burst to maximize this effect is 4.87 km.
Thermal radiation radius (3rd degree burns): 22.3 km (1,560 km²)
Third degree burns extend throughout the layers of skin, and are often painless because they destroy the pain nerves. They can cause severe scarring or disablement, and can require amputation. 100% probability for 3rd degree burns at this yield is 12.2 cal/cm2.