Errors of a Simple Doppler Computer due to the Spheroidal Form of the Earth

J. E. D. Williams
1960 Journal of navigation  
Doppler-operated computers which perform plane D.R. navigation are currently offered to the airlines. A datum track and distance to go are set; from the time of selecting ON, the computer resolves small elements of distance run (input doppler and heading reference) as follows:Change in across-track dist. = element of dist. run × sin (actual tr. − set tr.)Change in along-track dist. = element of dist. run × cos (actual tr. − set tr.)These relations are true for a plane Earth.
doi:10.1017/s037346330003366x fatcat:qlk7qtjalbbq5kkk6wvc2aib44