where:

..\Images\INFO0854_wmf.gif

is the rudder trim tab deflection angle.

..\Images\INFO0855_wmf.gif

is the additional rudder tab deflection angle required to trim the aircraft .

..\Images\INFO0856_wmf.gif

is the rudder tab gearing ratio.

..\Images\INFO0857_wmf.gif

is the rudder deflection angle.