President Barack Obama and his wife Michelle (wearing Preen) stepped down from Air Force One, after arriving at Stansted Airport, near London, late Monday, May 23, 2011. Obama is in London well ahead of schedule after concerns over an ash cloud spreading from a volcano in Iceland sped up his travel plans. Obama had planned to spend Monday night in Dublin and travel to London on Tuesday morning. But White House officials say the ash cloud changed course, forcing Obama to leave the Irish capital early.