Just off the top of my head
(Actually I copied this from a book I wrote on formation flyoing a while ago.)
Turn theory shows in steady, turning flight, the horizontal component of lift must equal the centrifugal force. This fact allows the development of the following formulae. The radius of a turning aircraft is given by:
Code:
r = Vē
-----------------------
3.78 g tan * and the rate of turn is determined by:
ROT = 111 g tan *
-----------------------
V
(Where: r = turn radius in meters, V = velocity in knots (TAS), * = bank angle in degrees, ROT = rate of turn (degrees per second), g is the acceleration due gravity (9.8 m/sē) and the constants are included so that V is expressed in knots rather than m/s.