ok so this is a bit embarrassing but figured id post it because maybe someone else can learn from it. was doing a flat commercial roof inspection last week, big warehouse type building, maybe 400ft x 200ft footprint. fairly windy day, probably gusting to 18-20mph which i know is pushing it but the client had a tight schedule and i figured i could manage

im flying a manual grid pattern because my usual automated mission app was doing something weird with the waypoints and i didnt want to troubleshoot it on site. about halfway through i got distracted checking the live feed for a membrane tear i thought i spotted and drifted way closer to one of the big rooftop HVAC units than i realized. the vortex off the top of the unit basically grabbed the drone and shoved it sideways, hit the side of the HVAC housing, lost two props, drone dropped about 6 feet onto the roof membrane

luckily the roof wasnt fragile and the drone survived minus the props and a cracked arm. but it rattled me pretty good. i think the combination of wind plus not using a proper automated pass plus not paying attention to obstacles while also monitoring the feed was just too many things at once. anyway. anyone else had HVAC turbulence issues on rooftop jobs, or is there a standard clearance people try to maintain from those units

oof yeah HVAC units on flat roofs are genuinely sketchy especially if they have big exhaust fans running. ive made it a habit to fly my first pass at maybe 30-40ft AGL just to map where all the protrusions are before i drop down for the actual inspection altitude. adds a few minutes but youre not surprsied by anything

also stopped trying to monitor the feed in real time while flying manually over obstacles, thats what the recording is for. review it after. trying to do both is exactly how you end up in your situation

this is why i pretty much refuse to fly manual grid on commercial roofs now, too much going on mentally. DJI Pilot 2 waypoints arent perfect but at least i can focus on watching the airspace and the drone instead of also trying to maintain spacing. what app were you using that had the waypoint issue, curious if its something ive seen before