U.S. Coast Guard Capt. Hung Nguyen, co-chairman of the Deepwater Horizon joint investigation hearing board, along with George Wheatley, senior investigating officer from Coast Guard Sector San Francisco, begin the second day of hearings, May 12. The Coast Guard and the Minerals Management Service are co-chairing the joint investigation launched to determine the cause of the initial incident and fire aboard the mobile offshore drilling unit Deepwater Horizon. (U.S. Coast Guard photo Petty Officer 2nd Class Thomas M. Blue)