The switch is right on the top of theTx, if you're going to land... Lower the landing gear after you've finished filming... If you're not filming, don't raise the LG!
If you've got time to choose the auto retract button (if it had one!) you could've flicked the switch to lower them!
If you've got time to choose the auto retract button (if it had one!) you could've flicked the switch to lower them!