23857122-0457-180273-0393

Ltr, ERH, to CG, ANC, Subjs Analysis of Proj. "Grudge" Reported Incidents The description of incident No. 40 is inconsistent with the appearance of balloon flight No. 11. Also, in consideratior of the prevailing upper winds, it is very unlikely that the balloons would have gone more than a few miles westward of Alamogordo, although it must be admitted that a long flight west of the launching point could not be ruled out as impossible. ce Incident No. 7 compares somewhat in time with balloon Launching No. 10 of 5 July 1947. However, balloon No. 10 although not recovored Was known to have been downed northeast of Albuquerque, New Mexico. It was not recovered due to impassability of terrain. Incident No. 113 is a reasonable description of the 20 ft. plastic balloon and instruments used by these laboratories. This incident was on the date of balloon release No. 46 of 9 April 1948 at Alamogordo. However, the time of the reported incident (1506 CST) is about i/2 hour before the time of balloon release (1432 MST), thus the incident could not have been that balloon. de It is of interest to note that incident No. 122 was report- ed by an employee of these Laboratories who had considerable experience in the use of balloons of all kinds, and could have been depended upon to know the appearance and behavior of a balloon if it was this he saw. e. Incident No. 163 bears a fair description of the appearance of a large plastic balloon in sunset light. The object's disappearance could be accounted for either by its movement into the earth's sunset shadow or by natural defocusing of the observer's eyes. This incident § , could possibly have been balloon release No. 75 or No. 76 or 20 and 21 July 48 from Alamogordo. Bulloon No. 75 was recovered at Hollister, California, which is in the Monterey Bay area, on 22 July 1948 and could have easily had a trajectory which would have been within sight of the Los Angeles area. Balloon No. 76 was never recovered, It is possible that it had a trajectory similar to No. 75. f. All other reported incidents from 1 to 172 do not seem to have reasonable comparison with balloons launched by these Laboratories, 3. The balloons used by these Laboratories are now somewhat standardized. They are 20 feet long, plastic, white in color, and hem sphereeon-cone in shape. Nearly all launchings are made at the Holloman AFB at Alamogordo, New Mexico. Two photograph prints are in- closed showing the appearance and size of these balloons. The larger photograph shows the typical flight appearance at any altitudes where it would be visible. It is hoped that this information may be of some use to you in identifying future reports of incidents. 2 S =34,560 Declassification Authority: NND 57565