A small airplane crashed in a rural residential area as it headed to a landing, killing four who were aboard the aircraft, authorities said Saturday. No injuries were reported to people on the ground. The crew of the twin-engine Cessna 340 had radioed their intention to land at the Erie-Ottawa Regional Airport in rural northwest Ohio at about noon, airport director Jack Stables said. He did not know where the flight originated. The two men and two women on board were killed, the State Highway Patrol said. Stables said he watched the plane fly across a field near the airport to begin the landing pattern. Its landing gear and flaps were down, apparently in preparation for landing, he said.