 After the signing of the Armistice on 11 November , which ended all fighting , O 'Brien transported mail and passengers between Brest , France , and Plymouth , England . She returned to New York on 8 January 1919 , but returned to European waters in May when she served as one of the rescue <unk> stationed along the route across the Atlantic flown by three Navy NC @-@ type seaplanes in the first aerial crossing of the Atlantic . 
