Having been in a car with a cigarette smoker who didn't understand that rolling the window down didn't magically sweep all the smoke out and keep the air clean, I can safely say that Romney is dumber than a 6 year old kid about this issue.
Also, even if it did, it'd also sweep all of the air out of the plane, too, as well as pretty much creating drag.
In other words, Romney didn't think this one out too much.