Luke, 3 oz will give you about 30 seconds of decent smoke!! you will need to squeeze a 8oz tank in if you want it to last a quarter if your flight and to fit a Pete t pump at about 3oz (guess) you are now creating yourself a nasty toy!! you will also have to fuel proof the entire airframe and all the covering joints very well and be prepared not to be able to pick the plane up after a flight (Sllliippeerryy