With the increasing interest in long distance SOTA, especially transatlantic, I think it is perhaps time to take another look at the distance/bearing calculations on SOTAwatch. I don’t know what formulae are used but the answers are fairly hopeless for long distances. For example I looked at the bearing from the UK to Carolyn’s proposed summit in W5, and was told 218 degrees. In fact the correct bearing is more like 305 degrees - a huge difference if you’re pointing a beam. The distance is also way out, though that has less drastic consequences.
It would surely be better to remove this facility than give wrong answers. However I don’t think the formulae for a spherical earth approximation are very complicated, and this would surely be good enough. I’ve no idea what it can be using now - possibly a flat earth model. Or maybe it’s just a coding error!