Standard Bearing Plot

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The Standard Bearing Plot was a well-conceived but tardy replacement for the original bearing plot used on Dreyer Fire Control Tables through Jutland. It's design goals appear to be a more compact dimension, better use of the paper for visual estimation of bearing rate, and enhanced integration with the Dreyer table as well as the outboard users of the table's gun deflection output.

Though the standard bearing plot is well documented in the Handbook for Capt. F.C. Dreyer's Fire Control Tables, 1918, this is actually quite misleading, as the devices never saw service to the extent implied. It is possible that the only ship using a standard bearing plot on its Dreyer table was Ramillies from July, 1917[1].

Schematic of the Standard Bearing Plot


The standard bearing plot featured

Inputs and Outputs

Inputs to Standard Bearing Plot
Input Source of Data Means of Expression
Own Ship's heading Gyro-compass continuously, by motor
Relative target bearing Optical instrument aloft continuously, by motor
Bearing 'cut' indication Button near target bearing indicator device momentarily, by electrical pulse
Gun range from Dreyer table's Spotting Corrector continuously, by shafting
Bearing rate bearing plot operator's use of rate grid by local bearing rate handle
Dumaresq deflection lining up with commanded deflection on dumaresq deflection drum by local bearing rate handle
Dumaresq Deflection (corrected for range) from local gun deflection drum by a handle on face of deflection totaliser
Deflection corrections spotters, Wind Dumaresq operator by handles on face of deflection totaliser

Outputs from Standard Bearing Plot
Output Destination Means of Expression
Gun Deflection T.S.'s Deflection Master Transmitter occasionally, by manual working of totaliser's chasing output handle
Dumaresq Deflection for cross-checking with dumaresq read from dumaresq deflection drum

See Also


  1. Brooks, John. Dreadnought Gunnery and the Battle of Jutland, p. 174.


  • Brooks, John (2005). Dreadnought Gunnery and the Battle of Jutland: The Question of Fire Control. Oxon: Routledge. ISBN 0714657026. (on and
  • Admiralty, Gunnery Branch (1918). Handbook of Captain F. C. Dreyer's Fire Control Tables, 1918. C.B. 1456. Copy No. 10 at Admiralty Library, Portsmouth, United Kingdom.