Section 5.47 - Coast Guard ensign(a)Description. The Coast Guard ensign is described in 33 CFR 23.15 .(b)Display. Vessels that have been accepted as facilities and that have a Coast Guard commissioned, warrant or non-commissioned officer onboard shall display the Coast Guard ensign in place of the Auxiliary patrol ensign while on patrol, whether or not the vessel is underway. The Coast Guard ensign must be displayed at the mast head or from the most conspicuous hoist.