The groundwork of practical naval gunnery; a study of the principles and practice of exterior ballistics, as applied to naval gunnery, and of the computation and use of ballistic and range tables . , anapparent shorteningof the trajectory, due to an apparent decreased initial velocityTTuid seCOlld, a bOdHycarrying ahead of this saiilt; UtlJecLory, clue Tdtlre Hiovcment of the medium in whichthe projectile is hred. ~~ Tn paragraph 236 we found that when considering the trajectory relative to mov-ing air, tlie resultant velocity V, for a positive wind, is less than V. The resultant is greater th
The groundwork of practical naval gunnery; a study of the principles and practice of exterior ballistics, as applied to naval gunnery, and of the computation and use of ballistic and range tables . , anapparent shorteningof the trajectory, due to an apparent decreased initial velocityTTuid seCOlld, a bOdHycarrying ahead of this saiilt; UtlJecLory, clue Tdtlre Hiovcment of the medium in whichthe projectile is hred. ~~ Tn paragraph 236 we found that when considering the trajectory relative to mov-ing air, tlie resultant velocity V, for a positive wind, is less than V. The resultant is greater than (f>, but since by formula (-t), page 28, A varies as the square of thevelocity, a change in velocity has greater eitect than a change in the angle of trajectory, apparently shortened l)y a decreased in velocity, will be OSH, asshown in Figure 20(6), falling short of the target il/ by a distance HM. Now the wind carries the projectile along in flight a distance WxT, so that thetrajectory 067/ may be represented as taking up a new position OSJI, the projectilefalling at H, a distance W/F ahead of point H. The distance beyond the target Mwill then be i^X^X+^ Figure 20(&) If we had considered a negative wind, we would have obtained the same result in thi^fo™ -AZ= + X 239. The process just explained is not only a somewhat lengthy and inconvenientone, but the methods of interpolation used with the ballistic tables were not devisedwith this particular process in view, and do not produce results sufficiently accurateto determine the small differences in range with the precision necessary in this classof problem.* A carrying out of the process just described may therefore not bringcorrect results, and it is desirable to reduce the formulae, if possible, to some formmore convenient for practical use and that will not involve the use of the ballistictables. Although, as already stated, the above formulaj are not useful for obtainingpractical results i
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectballistics, bookyear1
