Blast Mtg Notes, 29 Dec 51 I. Pressure-time at Various Altitudes (Smoke-puff Photography ) 1. are proposed. High Altitudes (Guns) Ten guns to launch smoke to cover five areas for photography These areas would be as shown in Fig. 2. It was agreed to LoS 232) 4 }),000 10. cow} ~ Eiveo \ 77 / Ground Fig. 2 to place them on Bogon; Porzel said recovery of the launching guns wae not essential. The cameras will be on Rigili. Timing signals will be required to fire the guns, and a concrete pad to hold the trunions will be necessary. Zadina suggested another vertical. line--say, on Engebi-~ to really track the propagation of the blast wave and to get a notion of its Geparture from the hemispherical. Ogle questioned that another line would accomplish this. As a compromise, one extra point was suggested instead. This would require another camera, or might be done by sacrificing one of the points in the vertical line and using that gun to place the smoke in a different position. However, this must be decided before the camera station is erected, since the camera positions are being built in. One fundamental difficulty with this measurement is the fact that cloud coverage may result in complete loss of data. However, since the method is the simplest way of obtaining the information sought, it is felt the chance 1s worth taking. 2. Low Altitudes (Firevorks ) Here, small paper mortars will be used to launch smoke puffs to a few hundred feet; again, photography will be from Rigili, Felt suggested that the smoke should go to 500 ft, if possible, since 200 ft, as first planned, would be right on the horizon from Rigili. Porzel agreed.