My EZStar loiters fairly well with no wind. However, the other day I went up in 12 mph wind for the heck of it and found loiter to be way off the mark. The circle was almost flat on the up wind side, right over home and an ellipse on the down wind side. I realize this may be asking beyond technical capability but is there a way to tune better for stronger winds?
Its going to be a function of the capabilty of the aircraft any wind speeds more than 50% of the cruise are going to be an issue as the platform does not have the grunt to get smartly round the corner. I am flying my Talon at 50 mph and I would expect issues starting at 25mph this is thumb suck number that experience shows holds to be true.
So my answer is get a faster platform for windy days.
Check the roll angle in your logs. It is likely it is hitting the bank angle limit on the downwind part of your loiter, so there is nothing the autopilot can do to turn tighter. If that is happening your options are some combination of the following
a) increase the loiter radius
b) increase the maximum bank angle
The tightest loiter radius that a plane can fly with a 45 degree bank angle is given by the formula:
radius = (airspeed + windspeed) * (airspeed + windspeed) / 9.8
airspeed and windspeed are in metres/sec
radius is in metres
A model flying at 16 m/s with a 8 m/s wind, requires a loiter radius of at least 60m