S G. W. Johnson contpennnll Page Five COPAA~317 and proof of scientific gear and stabilized platforms. to Transit time E.P.G. Phase I could be accomplished anywhere feasible on the U.S. Pacific Coast but it is preferable to accomplish this phase near Livermore, if practical, to expedite and coordinate diagnostic equipment design. Again, with the thought that the ship is an AEC scientific station, we request that Holmes and Narver assume the responsibility as an AEC contractor for the design and execution of the shipboard modifications necessary to fit her out for our purposes. This channel is established between Task Groups 7.1 and 7.5 and we wish to follow it in handling the ship modifications. The build up of civilian crew and some buildup of H&N personnel aboard can be accomplished, from our viewpoint, during Phases I, II and III. It is planned that only a few diagnostics personne] would make the trip from the Z.I. to EPG aboard the ship. The technical requirements aboard also include the necessity for the installation of the firing racks, weather radar, release tone equipment and other items essential to the detonation of a nuclear device by radio. All of this equipment mst be in an air conditioned space subject to both temperature and humidity control. Such equipment has been housed in a room with an area of 300 square feet. It is essential that this equipment be aboard the same ship as the diagnostic equipment for reasons of interlocking and close coordination with the diagnostics and weapons group representatives during firing. The most important technical requirement comprises the clear deck area and its elevation above the water line in which diagnostic equipment can be mounted on stabilized platforms. Designs of the scientific equipment are not yet finalized but certain design parameters are mown. These parameters define the space fairly well. . 1. 2. 3. 4 5. A maximum of six stabliized platforms are required. Weights to be carried on these platforms range from approximately 100 to 2,000 pounds. All platform areas must be at least 20 feet above the waterline. Two platform arees mat be at least 60 feet above the waterline. The axis of the equipment placed on these platforms mst te stabilized in continual coincidence with a line of sight toward the zero site to an accuracy of +30° divergence. : Considerable information has been gathered on the possibility of using radar tracked gun mounts for this purpose. Most, but not all, of the weight loads to be accommodated are compatible with placement on a 40 mm qued-mounting. We feel that at least one of the mounts should be larger than a 40 mm quad. The U. S. Navy at Mare Island has forwarded an estimate for the placement of a 40 mm twin mount on the flight deck of a CVE as follows: ,