CHAPTER I!, SECTION 3 Twelve trailers and 8 generators furnished and installed by the Users were known as Station 550.01. The trailers were grouped in three, at four locations within a 50’x 320’ cleared and stabilized area. A 16’x 16’ storage tent and forty-eight 6” x 6” x 6” high blocks for generator supports were provided. Main and spare count-down outlets were furnished. Timing signals for minus 15 minutes and minus 1 minute to use removable baffled-end panels. Each baffle consisted of two removable panels back-to-back with 8” steel horizontal channels alternating in vertical positions. It was anticipated that the baffles would eliminate any possibility of reflected pressure within the housing andstill allow the air to circulate. As an added pre- caution against inundation, the generator sets were mounted on the roofs of the concrete and a blue box were required. A total of 4 buildings. STATION: Power to these stations was supplied by two 20 KW, 120/208 volt, 3-phase, 4-wire, 60- cubic yards of concrete was poured. PURPOSE: 560.01, .03, .04 and .05 Aircraft Positioning, Raydist Relay Stations SITES: Able, How, Nan and William USER: DOD-5 PARTICIPATION: 10, 11, 12, 13, 18 and 23 CONSTRUCTION: 1-11-56/5-5-56 OCCUPANCY: 4-9-56 Each station consisted of a reinforced concrete building and either a four or eight-antenna tower array. The building for Station 560.01 was 18’ x 33’x 13’ high with 4-foot thick walls and slabs. To allow for reflected pressures hitting the side of the building, the foundation slab was extended 5’ out from either side to prevent overturning. Station 560.01 served as Station 150.01 for the Cherokee event. The buildings for Station 560.03, .04 and .05 were 18’ x 33x 13’ high with 1 foot-thick walls and slabs. Each structure had three blast resistant doors designed to be watertight. One was a 2’10” x 6’ steel framed door and the other two were 20’-square steel doors for ventilation. These smaller doors were hinged at the top and trig- gered to close by means of an assembly containing an explosive link. A 7’x9’-high earth berm around each station prevented inundation of the tower footings and buildings. In the case of Station 560.01, the outer face of the entire berm was covered with sandbags containing a sand-cement mixture. After being set in place, the bags were wetted down to form a mat. At Station 560.05, the side of the berm facing the shore was covered with riprap. It was thought that riprap provided the more stable facing, but since it was not readily available at the Station 560.01 site, sandbags were substituted. At Stations 560.03 and 560.04, the nature of the an- ticipated wave was such that it did not warrant reinforcing the face of the berms. To protect the engine generators from pressures, the two units at each station were equip- cycle diesel engine generators. To ensure uninter- rupted power, the generators were run in parallel when the stations were abandoned. Each control panel had a reverse power relay which auto- matically cut one generator out in the event of operational difficulties. Two 12-circuit breaker distribution panels were installed in the stations, one for utilities and the other for scientific loads. Each panel was connected to one 20 KW generator so that when the machines operated separately, each unit furnished power to one panel. With this setup, all surges caused by utilities were limited to one generator, while the other unit supplied power to the scientific load free of voltage disturbances. The generators were run separately while the stations were set up andtested. Eighteen 30-amp, 120-volt receptacles were installed for scientific instruments. The connected loads for scientific and utility purposes, respectively, were 18 KW and 5.6 KW. Since power was required for scientific instruments through zero to at least plus 60 minutes, an automatic signal-actuated timer was designed to shut down the generators at 90 minutes past zero. The timer was actuated by a minus-one-minute timing signal. A No. 8 AWGsolid copper ground bus was installed above the work benches. The bus was connected to two ground rods, two generator neutrals, and the electrical conduit system. Inasmuch as the stations were equipped with blast doors, automatic shutdown was pro- vided for the ventilation equipment. Conduit and wiring were installed for two blast doors. No signals were required except for utilities. Four pair of signal lines were provided, three for the three signals required and one spare. A 16-pair terminal cabinet for signal and telephone ped with a steel-framed shelter utilizing rigid 5’ and one telephone were installed. air. This presented the problem of keeping the ends protected from pressures. It was decided Ventilation was accomplished by installing a 3,200 CFM blower. Aluminum ducts were installed around the work bench bases for exhausting battery fumes. Three 20” filters were high frames. The sides and top were covered with removable steel plate. The ends, however, were left open to allow for exhaust and clean Page 2-74