"d&tm" wrote in message
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"Grumman-581" wrote in message
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On Wed, 10 Jan 2007 00:03:22 +1100, in ,
d&tm wrote:
bank angle = tan ^-1 ( 2*PI*v / g *t )

v= velocity
g= gravitational acceleration
t = time for 360 degree turn rate
PI =3.14159
make sure you use consistant units for v, g and t
for SI use v in m/s
g = 9.8 m/s^2
t in seconds

in imperial g = 32 ft /s^2 ( If I remember correctly)
v in ft/sec
t in sec

Thanks Terry... Couple of questions though...

1. Is the resulting bank angle in radians?
2. Does the formula for the bank angle actually have "2*PI*v / g*t"
in it or was it supposed to be "2*PI*v / (g*t)"?

The bank angle is in what ever units you want. it is the angle expressed
as
degrees or radians that gives a tangent of 2*PI*v /( g*t)
(sorry I should have put in the brackets)
check your equation with a standard rate 1 turn. At 100kts a rate 1 turn
will have t =120 seconds and give a bank angle of 15.4 degrees.
terry
As an approximation
speed in metres/second is half speed in kts eg 100kts is about 50m/s
actually it is 52m/s.