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Proceedings - United States Naval Institute
Proceedings United States Naval Institute Author:United States Naval Institute Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: [oornianm.] U. S. NAVAL INSTITUTE, ANNAPOLIS, MD. NOTES ON FIRING INTERVAL, WITH EXAMPLES. By Lieutenant Charles B. McVAY, U. S. Navy. (i) Were a gun mo... more »unted on shore and fired at a stationary target, a telescope sight being used, then: If the gun returned to battery in its original position (which assumes that there is no movement of the mount), the gun- pointer would see the target in its original position in the telescope field. If he watched the splash of the shot in the field and placed the target at that point for the succeeding shot, he would score a hit. Suppose the target to have been placed at the junction of the right vertical and horizontal wires and the splash noted at x (Sketch i). This would show that the shot was high and to the right. If he now put the target at x, it would be necessary to lower the muzzle of the gun and train it to the left, correcting his errors. This is impracticable for a gun-pointer on shore, as the gun will not return to its original position; and is absolutely impossible at sea because the ship moves a considerable distance (1.7 feet for each second of flight at speed of I knot) between the times of firing and shot striking, as well as the fact that the ship rolls or yaws through a considerable angle, as will be shown later. It might be possible, however, for an observer, with a telescope similar to the one mounted on the gun, to stand behind the gun and, keeping the target in the proper position, to note the splash. For instance, if both telescopes were notched for every 5 knots For part of data I am indebted to Professor Philip A. Alger, U. S. Navy and Lieutenant L. C. Bertolette, U. S. Navy. speed on horizontal wires, and had similarly spaced notches on vertical wires as in Sketch 2, and the gun was Fired when...« less