I have been reviewing the entries in the diary of F/Lt J.A. Anderson DSO DFC of 419 Squadron for his operations and I am trying to reconcile the differences in distances that he records for his operations with my estimates for the sum total distances between all turning points. In all instances his estimates significantly exceed what I calculate using trigonometry for "Great Circle" distances between turning points. Has anyone encountered any calculated distances between turning points in any historical documents from Bomber Command?