Torpedo Data Computer: Difference between revisions

Revision as of 18:31, 18 April 2019

Revision as of 18:34, 19 July 2019

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*comparing the predicted position against the actual position and correcting the estimated parameters as required to achieve agreement between the predictions and observation. Agreement between prediction and observation means that the target course, speed, and range estimates are accurate.

Estimating the target's course was generally considered the most difficult of the observation tasks. The accuracy of the result was highly dependent on the experience of the skipper. During combat, the actual course of the target was not usually determined but instead the skippers determined a related quantity called "[[angle on the bow]]." Angle on the bow is the angle formed by the target course and the line of sight to the submarine. Some skippers, like the legendary [[Dick O'Kane|Richard O'Kane]], practiced determining the angle on the bow by looking at [[Imperial Japanese Navy|IJN]] ship models mounted on a calibrated [[lazy Susan]] through an inverted binocular barrel.<ref name="Okane">{{cite book | last = O'Kane | first = Richard H. | title = Wahoo: The Patrols of America's Most Famous World War II Submarine | origyear = 1987 | edition = Bantam | year = 1989 | publisher = Bantam | ___location = New York | isbn= 0-553-28161-5 | pages = 108–109 | chapter = Part 4: Chapter 1 }}</ref>

To generate target position data versus time, the TDC needed to solve the equations of motion for the target relative to the submarine. The equations of motion are differential equations and the TDC used mechanical integrators to generate its solution.<ref name=CBC>{{cite web | last = Bromley | first = Allan | title = Analog Computing Devices | work = Computing Before Computers | year = 1990 | url = http://ed-thelen.org/comp-hist/CBC.html | accessdate = 2006-07-22 }}</ref>