You can, for both DJI and Autel (the largest commercial manufacturers). There is similar functionality for the homebrew flight controller firmwares out there (e

You can, for both DJI and Autel (the largest commercial manufacturers). There is similar functionality for the homebrew flight controller firmwares out there (e.g. iNav/ArduPilot). I'm most familiar with Autel's system, since that's what I fly 99% of the time. It has the option to update your home point, but it also has two modes: RTH to takeoff point, and RTH to the controller. RTH = "Return To Home" The problem with all of the above is the "failsafe". If the quad loses connection to the controller, by default it will return to the takeoff point and land. You can set it up to RTH to either the the takeoff point or the last known position of the controller, then land or hover until connection is re-established. On a boat, you're constantly moving. If you lose connection, the drone immediately loses the current position of the controller, so you have to turn the boat around, manually find the drone, and cross your fingers that you're able to reconnect to it before the batteries die and it descends into a nice, slow, controlled landing in the middle of the ocean. Identifying alternate safe landing sites before taking off is part of the pre-flight checklist for any flight, but it's especially important when operating over water. Doubly so if you're taking off from a boat. Whenever possible, I make sure to end my flights with enough battery that I can make it back to land if I have to. I've planned to use (inactive) oil platforms in the Gulf of Mexico in an emergency. I have no idea how I would have gotten ahold of the owners and gotten access to it to retrieve my drone if I'd had to use it, but I'd rather work out those details later than lose it or be forced to ditch it in the water.