UPPER DARBY, Pa.—A pilot crash landed a medical helicopter Tuesday without casualties in a residential area of suburban Philadelphia, miraculously avoiding a web of power lines and buildings as the aircraft fluttered, hit the street, and slid into bushes outside a church, authorities and a witness said. None of the four people on board, including an infant, sustained life-threatening injuries, Upper Darby Police Superintendent Timothy M. Bernhardt said at a press conference, adding that he was eager to shake the pilot’s hand for getting the helicopter down the way they did. Rescue crews rushed to the wreckage by the Drexel Hill United Methodist Church in Upper Darby at about 1 p.m. and helped get the pilot, two crew members and the infant patient out of the aircraft, Bernhardt said. The infant was taken to a hospital as authorities worked to notify the child’s family, Bernhardt said. The flight originated out …