we use transformer oil in our 802 also we may try the form oil next time, we get it in 55 gallon drums though, some ag pilots do use automatic tranny fluid for the smoker too, the transformer oil somkes very well but again we are pumping it into the exhaust of a 1300shp turbine too, dunno about a model but im going to try it on one when i get an airplane built that i want smoke on., a friend of mine he flys a sukhoi 26 (full size) and actually uses the super dri model smoke for his airshow routine,