so ive been doing contract spraying work for a couple seasons now mostly with a T20P and been thinking about upgrading to the T40 because the tank capacity is just not cutting it anymore on larger fields. the 20L goes fast and the constant refill stops are killing my efficiency, especially when im doing fungicide passes on corn at like 10-15 GPA.

my question is more about the actual on-the-ground workflow with the 40L tank. does anyone have a good system for keeping up with refill pace? like are you running two mixing/loading stations? i feel like the drone can now outpace what one person can reasonably prep and load, which wasnt really a problem with smaller tanks. also curious if the coaxial rotor setup causes any drift issues differently than the single motor setups when youre doing the low passes close to canopy.

not looking for spec sheet stuff, genuinely want to know how people are handling this in the field

yeah the T40 is a beast but you are 100% right that the bottleneck shifts from the drone to your ground crew once you go that big. we run two 500 gallon nurse tanks on a trailer pulled right alongside the field edge, and even then you need someone dedicated to just doing refills. the drone can realistically pull ahead of one person loading if youre not organized about it.

on the drift thing, honestly i havent noticed it behaving drastically different than single rotor setups for canopy penetration but the downwash pattern is wider which can be good or bad depending on crop canopy structure. on soybeans we liked it, on tight corn rows at full tassel it got a little weird with coverage at the edges. mostly fine though. the real learning curve was getting the spray rate dialed in because the flow sensors on the T40 are more sensitive and it will throw warnings if your mix is even slightly off viscosity from what you programmed.

not on the T40 yet but we demoed one last fall and the refill speed is actually pretty decent with the integrated pump if you have a proper setup. the issue we saw was more about mission replanning between tank loads because the operator was using the field maps from the DJI Ag app and it wasnt always resuming cleanly after a battery swap mid-field. might be a firmware thing, this was a while ago. the coaxial rotors def throw a different wash pattern just from a physics standpoint so worth doing your own test strips before you commit to a full application rate