Two Aer Lingus flights from the United States were struck by lightning while landing Saturday at Shannon Airport in western Ireland, the airline said. No one was injured on the flights, but the lightning slightly damaged the noses of both planes, preventing them from flying on to Dublin, the Irish capital, Aer Lingus said. One flight from Boston landed at Shannon Airport at 5:50 a.m., while the other one from New York landed at 8 a.m. Passengers bound for the Irish capital were taken there aboard another plane, the airline said. Return flights to the United States also were delayed as engineers examined both aircraft before returning them to service, Aer Lingus said.