I think it would be real easy to get approval, just don’t have any of it forward of the firewall, and the hose that is be covered in fire shield. I can’t quote chapt and verse but your not allowed to have flammable fluids not necessary for engine operation forward of the firewall.
We installed them in the crop dusters I used to build, for the S2R-H80 I built our own smoker, all you need is a tank and an RV water pump, small one.
We built turbines and with them there is plenty of heat even at idle, but I don’t know how much smoke a C-85 would make?
Smoke oil is also way overpriced too, all you need is high paraffin oil, apparently concrete form release oil works great.
Crop dusters use a smoker so they can see wind drift and see if their spray is going to drift where it shouldn’t.
You don’t want to defoliate cotton next to a turnip field if the wind is blowing towards the turnips for instance, or any other crop.
Ever seen a Huey smoke bird? They whole tail boom and tail rotor had oil dripping from it, there was a ring mounted just at the exhaust with spray nozzles, made an enormous amount of smoke, you had to see it to believe it.
I thought I could find a video, they used to do a fly by at Ft Rucker during graduation, but I couldn’t
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