as you will know the battery level remaining is displayed in the app and the UAV will estimate the remaining power and will start to do a RTH when it estimates that there is only enough power to make it back i have mine set at 30 percent for first warning and 15 percent for critical low battery keep an eye on the batt level when you fly and adjust your distance and height to make sure you can get home as reguards to flying in windy conditions this will always shorten the flight time because of the extra power needed to make headway always fly into the wind on your outward journey if possible and remember the higher you go the stronger the wind speed