CHAPTER Ii, SECTION 3 CONSTRUCTION: 2-6-56/5-4-56 OCCUPANCY: 4-9-56 Station 261.01 was composed of two re- inforced concrete launching pads, each 100’x 12’ x 1’ thick, with surfaces finished smooth and located with the axis of each slab normal to a line through Station 18. Three bench marks were located in each slab. The orientation was accurate to plus or minus 5 degrees and had to be known to 30 minutes. No obstruction was allowed 15 degrees above the horizontal from the launcher site toward Stations 11, 18 and 22. _ The launcher site was located within a User- approved area which required a minimum of ground clearing resisting anticipated pressures. The blast door was watertight for protection against inundation. A work bench wasinstalled along the walls. The criteria for power at the relay station called for 110 volt, single-phase, with a peak demand of 30 amps. Power was required through zero time to approximately H plus 30 minutes. Two 5 KW portable generators supplied the power thru an automatic transfer switch. Timing for Stations 11 and 12 was minus one minute and minus one second; for Station 18, minus five minutes and minus 2.5 seconds, plus a User-installed photocell-operated timing signal. A temporary facility for 15 rockets was erected consisting of a squad-type tent with a concrete floor; a portion of the tent was used for office space. The tent was removed prior to and reinstalled after the Cherokee, Navajo, and Apache events. Four portable-type duplex receptacles of 120 volt and 20 amps pluslights and two large CO2 fire extinguishers were installed. Because of post-zero power requirements, special consideration was given to the engine generator sets. A 3’ x 6” high steel-frame shelter was constructed for each of the two 5 KW gasoline engine-driven sets. The sides and top of the shelter were covered with removable steel plate but the ends were left open for ventilation. To protect the open ends from expected pressures, baffled, removable panels were used. Each baffle consisted of two panels back-toback with 8-inch steel horizontal channels alternating in vertical positions. It was anticipated that the baffles would eliminate reflected pressures within the housing and still permit ventilation. The generators were mounted on the roof of the station as a protection against in- undation. The connected load was 4.8 KW. A six-circuit panel mounted in the station distributed the power within its interior and also to the adjacent tent. A special engine shutdown timer permitted the generators to run through zero and be automatically stopped at zero plus 90 minutes. The timer was operated by the minus one minute timing signal, which started a time clock set to stop the generators at any Figure 2-51. Station 261.01 pre-set time. Running time of 24 hours after zero was available on the clock. A 16-pair terminal cabinet with 4-pair sig- For protection against inundation, an em- bankment was constructed immediately in front of the concrete slabs with the toe of the slope approximately 8.5 feet from the first slab and with a height of 5’, which provided protection on the front and sides of the launching area. A reinforced concrete building for use as a timing relay station was constructed which was 8’ x 10’ x 8’ high, with 12”-thick walls and slabs, and equipped with a blast door 2’ - 10” x 6’ for Page 2-68 nal and 2-pair telephone lines was installed in the station. A total of 63 cubic yards of concrete was poured, with an average strength of 3,400 psi. Bronze marker plates were set in the concrete to give elevations and orientation. STATION: PURPOSE: 262.01 Cloud Sampling with Rockets