this has been driving me nuts for the last two weeks. running an XAG P100 Pro on wheat, set up AB lines in the field management software and the drone is consistently drifting maybe 1.5 to 2 meters off the planned swath on certain passes, not all of them which is whats confusing me. coverage gaps are showing up in the crop which kind of defeats the whole point.

conditions when it happens seem to be when theres any crosswind over maybe 10-12 kph. im wondering if the RTK positioning is actually solid or if i have a base station placement issue, the base is sitting on a trailer at the field edge and i didnt do a super careful site survey before setting up. could also be the spray boom pressure affecting flight stability i guess? tank is full at the start of those passes so its heavier

anyone dealt with drift like this on a spray platform, is there a setting im missing or do i just need to dial back the mission wind limits

almost certainly your RTK base placement. if the base unit isnt surveyed in properly or is getting multipath interference from the trailer body or anything metallic nearby your fix quality is going to be garbage on certain headings and the aircraft just doesnt know any better than what it's getting from the correction stream. try moving the base well away from the trailer, ideally a proper tripod on open ground, and check what your fix status is actually reading during flight ? should be fixed not float.

the weight thing from a full tank can affect attitude compensation a bit but the XAG handles ballasting pretty well in my experience and 10 kph crosswind shouldnt be causing 2m deviations if your RTK is solid

had almost the exact same thing happen on a P40 last season, turned out to be partly the base station issue the other guy mentioned but also my spray parameters were set for a lower flow rate than what i was actually running and the boom pressure was creating asymmetric thrust compensation issues. not sure if thats a factor on the P100 but worth checking if your actual output matches whats configured in the task settings. XAG support was actually pretty responsive when i sent them logs, might be worth pulling the flight records and sending them over if you cant figure it out