You can buy a plane that uses a piston engine running on leaded gasoline and fly it all day long, as long as you want. You need to stay out of restricted airspa

You can buy a plane that uses a piston engine running on leaded gasoline and fly it all day long, as long as you want. You need to stay out of restricted airspace, but that applies to all aircraft. This dumps lead into the atmosphere nonstop while taxi'ing and while in flight. The only limit on this activity is the depth of your wallet.