The USCG has several sets of classes of ships, informally known as black, white and red hull. Black does what you say, white does border patrol for drugs and p

The USCG has several sets of classes of ships, informally known as black, white and red hull. Black does what you say, white does border patrol for drugs and people illegally entering the country, and red is scientific and icebreaking. See http://www.uscg.mil/proceedings/spring2011/articles/10_Tlapa.pdf http://www.uscg.mil/proceedings/spring2011/articles/10_Tlapa...