Operation TUMBLER, Nevada Proving Grounds, April-June 1952, Project 1.4, Air Blast Measurements.
Abstract
The objective of Project 1.4 was primarily to determine the general shape of that portion of a shock wave propagated near the ground but originating from an atomic explosion high in the air. Secondary objectives were the calculation of peak pressures involved and the computation of a blast efficiency for each bomb. To achieve these purposes the shock arrival time method was used with blast switches at three levels above the ground both in the regular reflection and Mach reflection regions. The air shock arrival times clearly indicated that the free air shock velocity was higher in the layer from 10 feet above the ground to ground level than it was in the layer between 50 feet and 10 feet above the ground. The increased velocity near the ground is probably due to a heated layer of air near the ground caused by radiation from the bomb. On Shot 4, the air shock arrival times corroborate the existence of a precursor shock as observed by other methods. In the Mach region the shock front appears to be vertical between the ground and 50 feet in the air. The pressures calculated for Shots 1 and 4 in the Mach region are in fair agreement with curves presented in Supplement 1 to the Capabilities of Atomic Weapons. The blast efficiencies of Shots 1 and 2 were of the order of 62.7 percent and 68 percent respectively. No blast efficiency was computed for Short 4 due to the lack of free air data.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1952
- Accession Number
- ADA078547
Entities
Organizations
- Ballistic Research Laboratory