_—— =SEFRIT = PROGRAM I Project 1.1 = Basic Blast Measurements = Charles Kingery =~ BRL The primary object of this project is to obtain basic blast measurements; this will be in the form of air blast pressure time records, dynamic pressure time records from various yield detonations. series: We will instrument six of the following Cherokee, Pueblo, Zuni, Yuma, Lacrosse and Mohawk. The BRL self-recording "Pt' gauges will be used throughout and be installed at ground level at various distances from GZ. All surface stations on islands will be installed by BRL personnel, The BRL self-recording "q" gauge will be installed 3' above the ground surface on all land stations and 3! above the mean tide on all the reef stations. The main effort will be on Cherokee where we expect to make a total of 30'Pt" measurements and 11 "q" measurements. Zuni will be the next major effort; will have gauges on the Tare complex and Uncle Island; we expect to take a total of 2, ‘Pt! and 10 "q” measurements, The "q” measurements will be along stations where we plan to put jeeps to measure the dynamic pressure present at those positions. On Pueblo, Mohawk, Lacrosse and Yuma will have limited number of stations and blast lines will be installed on each to obtain pressure distance curves, We plan to cover on all of these pressures which are of military importance. There will be 12 people in the FA = eight civilian and four military, Project 1.2 = Thermal Effects = A. D. Thornbrough = SC To determine if a precursor is formed from a medium-sized surface burst. The project will measure overpressure and dynamic pressure at several distances from GZ. Wiancko pressure gauges and pitot tubes will be used as on past operations; the recording system will be similar to that used on Operation CASTLE. A total of 10 channels, six Delta "P's" and four "Q's" will be instrumented for the Lacrosse shot on Yvonne Island. We will share the shelter with Project 30.1. Project 1.3 = Shock Photography = Peter Hanlon = NOL We plan to participate in four shots - on Cherokee, Pueblo, Zuni and Mohawk with emphasis on Cherokee on which shot we plan to measure free air pressure distance at burst height and in the regions above the burst point, and to study the effect of surface heating of the air near the surface on shock wave propagation, and to check scaling, and determine the blast yield of a Mt weapon free from influencing surface effects, and also to make an effort to study the effects of non-= homogeneous atmosphere on blast transmission. For Pueblo and Zuni, both of which are land shots, we intend to make a determination of the pressure both along the surface and vertically above GZ and to study the effects of the surface and surface heating on shock propagation. On Mohawk a function is to study the effect of a vegetated surface on shock growth. —