At 1530 mountain time, a Helio H800 struck the ground 200 feet from the approach end of runway 22 at the Yellowstone Regional Airport. The pilot sustained minor injuries and the three passengers reported no injuries. The airport manager said the airplane took off on runway 04 and started spitting oil. The airplane got to about 300 feet agl when the pilot returned for landing. The witness said he noticed the oil cap was off the engine and the oil stick was out.