BOAC
I have never used 'DR' on low-level nav. I do not know of the practice
.
Flying visually in inclement weather towards the coast can lead to untold problems if you do not know when you expect to get there. A minute early - disaster............
So..............DR
DR - Simple really - time/distance. (Dalton computer). Coasting in from the sea towards the land ,work out when you expect to get there by the old fashioned methods and keep that in the back of your mind as you near the coast. A reliable cross check on your hitech nav gear. If the weather is dodgy as you reach your DR lower regions tightening point, do something. Slow down, descend, airtaxi, turn round or whatever. Don't blunder on. I guess you have never coasted in to an unknown shore in the dark when it is snowing. This is not points scoring - but the time/distance calculation is so simple and such an effective safety belt. It can and has averted disaster on many occasions.
Keep flying safely.
All the best.
