Just so you understand, if you fly out from the top of a mountain and get more than 400ft AGL it will be just as illegal as if you launch and fly upward 450 feet (whatever). So there is that. The drones that can't fly over 500m are still limited by that - at least that is my understanding from a variety of sources. I have not yet tested it. I have a nearby hillside (well..not that nearby...) that I have broken that 500m limit on with my Mav 3 and Mav 3 Pro by "climbing" up the side, remaining 400ft AGL (at least with my best guess of it). I -think- that limit has not changed. That has been said by several people so I'm reasonably confident that is the case. I'll have to give it a try next time I'm at my fav hillside. If you're in a position to fly out from a mountain you probably have a good view and know there are no planes anywhere near and odds are there are no houses or people nearby. You can fly safely in such a case but it may still be illegal. That, for me, is the biggest issue I have with the FAA rules. There are no exceptions for breaking the basic rules when it is 100% guaranteed safe. Oh well. I figure in a few years this will be considered the "golden age" of droning before even further restrictions are implemented and drones are no longer even sold to commoners like myself

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