I've never seen so much talking in circles over a fairly basic matter. May I endeavour to provide 3 practical conversions for day to day use?
(1) Calculation of Rate of Descent for a given Gradient in %
ROD (fpm) = % Gradient X Groundspeed
(2) Calculation of Rate of Descent for 3° Glide Slope
ROD (fpm) = 5.3 X Groundspeed (At Jet speeds, 5 X G/S + 50 fpm)
(3) Conversion of % Gradient to Flight Path Angle (FPA) degrees
FPA = % Gradient X 0.6
Simple isn't it?
enicalyth, surely a man of your calibre would use 1 nm = 6076.1155' (just being my pedantic self).
Regards,
Old Smokey