Ships stopped allowing travel Irons years ago.   I now pack a kettle steamer on long trips where I need formal wear (not going to have suite and shirt pressed for each formal night).   When I pack it in my checked luggage never a problem.  On one trip when we did carry my buddy was stopped and told he could not bring a steamer on board (Carnival in Long Beach,  but Carnival in Miami let it stay in my large suitcase that I carried on myself)