D : 51.1234 (sometimes called decimal degrees and not shown with the ˚ symbol)
DM : 51˚7.24.4' (sometimes called decimal minutes and common format of older navigation systems like Skymap)
DMS : 51˚7'24" (sometimes called DMS and the original format based on 1/60ths)
Many aviation documents and sites use DMS whilst all modern online mapping sites have adopted D. Please note, all printed charts have DMS marker lines so the DMS format is useful for quickly finding a location.Â You may find you need to convert between the two. Actually, you can quite easily do an approximate conversion in your head e.g. 51.5 is 51˚30'.
Helipaddy pilots are able to select their preferred format straight from the app in a few simple steps. To change coordinate format in-app, select account in the burger menu on the right-hand side of the screen. Then simply select with coordinate system you would like and click save at the bottom of the screen.
Helipaddy recommends using the PGC coordinate converter when switching between systems: https://www.pgc.umn.edu/apps/convert/
Pro Tip: A degree of latitude remains fairly constant from the equator to the poles; however a degree of longitude can vary greatly as one approaches the poles (because of the convergence of the meridians.
See you in the skies!