Funny how my brain can do all that without having the first idea about V(sqrd)/G x Tan theta
As an ex colleague (known for his tact once said as the aircraft cocked up a turn on a centre fix) If
I'D done that you would have complained!!
Quite right too.
The only rule of thumb I have is if a
certain operator has more than one aircraft in the sky approaching the same point on an instrument approach they seem to use a random number generator to give them approach speeds!! (thanks Jo-jo)