CHAPTER 2 , EXPERIMENT DESIGN 2.1 GENERAL The experiment design consisted of sample plots and pressure measurements on three small naturally forested islands (Unele, Victor, and William) spaced along a radius bearing approximately 280° from Shot 3. These isiands spanned a desirable predicted overpressure region for the expected yield ranging from heavy damage to light or no damage. It was essential to the success of the experiment that a substantial portion of the trees as a group remain intact, giving a graded series of dunage in order to secure data in sybstantiation of previously develop:d breakage prediction systems.= ‘ The size of the stands and the range covered were dictated by the adequacy of vegetation and the radial, periodic orientation of the few available islands adjacent to Shot 3 island. Because of expected contamination by Shots 1 and 2 all project work for Shot 3 on the three islands except arming of the various gages was completed prior to Shot 1. 2.2 2.2.1 TREE STANDS Unele Island Uncle Island, largest of the three islands, west of the tidal inlet is 170 acres in area, and bore a dense cover consisting of coco- nut palm, Pisonia (a broadleaf tree), and several shrub species. Openings among the trees were covered with the grass Lepturus and the prostrate Ipomcea vine while the fringing trees were adorned with the liane-type vine Cessytha. Table 2.1 gives common and botanical names of the imvortant tree and shrub species on all islands and their relative cbundance. Figure 2.1 shows the Uncle Island stand from tae air prlor to Saot-l. Figure 3.5 is a view inside the >.aim portion of the seme stand, end Pigs. 3.4 shows the interisr of the Uncle Isleni stand. >orozdlesf norticn of 1/7A¥FSwP, UPSHOT-KNOTHOLE, Project 3.19. 16 SECRET -— RESTRICTED DATA