File Description: These are scenery bgl's to replace those previously posted for Cape Dorset, Gjoa Haven, Igloolik, and Whale Cove. All of these airfields are within what is marked on the chart as "Northern Domestic Airspace" and their runway signage is not given as a magnetic bearing but as a true bearing. This is because at those latitudes, close to magnetic north, the magnetic field is more vertical than horizontal and magnetic readings become unreliable. Planes report their course as a true course, and fly at a height that reflects their true course instead of their magnetic course. The picture shows the runway sign for Qikiqtarjuaq CYVM (which used to be called Broughton Island) which I am working on right now, and I realised that my training was so far behind me that I had forgotten all of the above. The boundary line of the two air spaces is not a straight line; the furthest south it reaches is on the west coast of Hudson Bay just north of Churchill. To the east it passes through the southern end of Baffin Island, and to the west it is north of the coast at the Alaskan border, and there is an illustration included here.