// angle of turn
double turn_rate = sin(roll) * SGD_PI_4; // radians/sec
double turn = turn_rate * time_step;
- double yaw = fabs(rudder) < .2 ? 0.0 : rudder / (25 + fabs(speed) * .1);
+ double yaw = fabs(rudder) < .05 ? 0.0 : (rudder * (fabs(rudder) - 0.05) / 10);
// update (lon/lat) position
double lat2 = 0.0, lon2 = 0.0, az2 = 0.0;