I would say, not necessarily SLR. Go for a Bridge - because everything is integrated there's limited ability to lose stuff , and they're fairly easy to operate single handed while flying with the other.
If you want a suggestion, try the Canon SX60. I use the slightly older SX50 , and have taken some superb photographs both on the ground and from the air. A cheap adapter allows you to fit filters, and it'll fit any of the usual mounts. I also have a radio remote control, designed for the more expensive SLRs that works with it and cost me £20 or so.
G