Thanks guys, some really useful advice. It's worked very well this week. I wasn't planning on using Pythagoras whilst vectoring(!) However my calculations seem to work that you need to add 1.5 miles onto the dme if you're 6 miles base. Turning base at 12.5 dme brought the aircraft perfectly onto the LOC 2miles before top of descent at 10miles. I presume radar controllers have range grids on the screen? I've only got a spiders web from the airfield and a 12mile extended centreline plus I can see the aircraft's navigation display and DME. Out of interest how do you guys calculate track miles to run? Do you just add 10 + 6 + 5 for final / base / downwind or do you have a more advanced way?
Cheers!