Plot 52º20’N 009º10’W, draw line from CRK through that position and draw
line from SHA through that position. Centre protractor on CRK and
align with magnetic north (use airway W10 053ºM radial); note radial
(328ºM). Centre protractor on SHA and align with magnetic north
(use airway G1 115ºM radial); note radial (212ºM).