Debris from a United Airlines plane fell onto Denver suburbs during an emergency landing Saturday after one of its engines suffered a catastrophic failure and rained pieces of the engine casing on a neighborhood where it narrowly missed a home. The plane landed safely, and nobody aboard or on the ground was reported hurt, authorities said. The Federal Aviation Administration said in a statement that the Boeing 777-200 returned to the Denver International Airport after experiencing a right-engine failure shortly after takeoff. Flight 328 was flying from Denver to Honolulu when the incident occurred, the agency said.