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    "localId": "486498244",
    "label": "Report, OSI - 10-50, Central Intelligence Agency, Soviet Guidance and Control Development Particularly as Applied to Guided Missiles",
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    "title": "Report, OSI - 10-50, Central Intelligence Agency, Soviet Guidance and Control Development Particularly as Applied to Guided Missiles",
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{
    "seq": 53,
    "pageIndex": 0,
    "type": "photo",
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    "ocrText": "TOP SECRET\nreversing its connections in the circuit of the accelerometer unit, so that the coated elec-\ntrode was negative. This caused the transfer of chlorine ions from the cathode to the\nanode, which then became coated with a quantity of silver chloride. The quantity of silver\nchloride transferred corresponds to a calculated value of S idt and hence velocity. The\noriginal connections were then restored and the cell was ready for use. The actual\naccelerometer could be used for this calibration since, when the rocket was set up in a\nvertical position, the pick-up arm was horizontal and subjected to a force corresponding\nto an acceleration of one g.\nIn flight, the freshly deposited silver chloride was transferred back to the\noriginal electrode, the completion of this operation being accompanied by a sharp rise of\ncell voltage, which triggered the control tube and operated the control relays. The rise\nof cell voltage was of the order of one volt and the time of transition about 0.01 second.\nSome cells were fitted with a bimetallic-type thermostatically controlled\nheater, to minimize errors due to variations in the solubility of the silver chloride by\nkeeping the temperature constant at 35° C.\nIn order to avoid the power consumption necessary to maintain the cells\nat constant temperature, a cell was designed to have a minimum of volume, since the\ndependence on temperature decreases as the volume of electrolyte is decreased. For\nthis purpose, a ceramic cell was produced, with flap portions of the ceramic silvered to\nform the electrodes. The first models built in this manner appeared promising but had\nnot yet been fully tested.\n(c) Gyroscopic Integrating Accelerometer.\nThe gyroscope type of integrating\naccelerometer (code name, Iller ) consisted of an electrically driven gyroscope mounted\nwith its axis of spin perpendicular to the axis of the missile. The gyro was suspended from\na single point which was not coincident with its center of gravity. Acceleration along the\naxis of the missile created a force through the center of gravity of the gyro. The result-\ning couple set up a precession of the gyro around its suspension. Also, when the missile\nwas vertical the force of gravity acting vertically through the gyro's center of gravity\nwould cause a further precession around its suspension. However, as the missile in its\npath along its trajectory assumed an angle A with the horizontal, the precession due to\ngravity would be proportional to g sin 0. Consequently the total angle of precession\nrepresented\nat\n/\ng sin A dt\nwhich term has the dimensions of velocity. Since the pitch-gyroscope controlled the angle\nO with respect to time, an allowance could be made for the second term and the controls\nset to operate at a preselected value of velocity along the trajectory. The gyroscope gim-\nbal drove a wheel which carried an electrical contact point. A second electrical contact\npoint was located on a movable plate which could be rotated to set the desired angular\nseparation between the electrical contact points. Settings could be made to the nearest\none-tenth degree. When the gimbal had precessed through the preset angle the electrical\ncontacts closed and the fuel was thereby cut off, in two steps.\n(6) Relative Use of Cutoff Methods\nIn tests at Peenemuende, cutoff was effected by radio control in about 50 per-\ncent of the cases, and by acceleration-integrating devices in the remainder. Radio control\nwas used in only about 10 percent of the rockets sent against England. Among the reasons\nfor this were the lack of sufficient ground radio installations and the increased danger\nof air attack while the ground crew operated the radio equipment. However, because of\nthe greater accuracy obtainable, the radio method was used until hostilities ended.\n3.3(b)(1)\nwhen\nradio control is used, the density of hits in a small area immediately around the target\nis greater than when integrating apparatus is used, even though the actual hits may cover\nTOP SECRET\n44"
}