# 117.4 Definitions.
The following definitions apply to this part:
*Appurtenance* means an attachment or accessory extending beyond the hull or superstructure that is not an integral part of the vessel and is not needed for a vessel's piloting, propelling, controlling, or collision avoidance capabilities.
*Automated drawbridge* means a drawbridge that is operated by an automated mechanism, not a drawtender. An automated drawbridge is normally kept in the open to navigation position and closes when the mechanism is activated.
*Deviation* means a District Commander's action authorizing a drawbridge owner to temporarily not comply with the drawbridge opening requirements in this part.
*Drawbridge* means a bridge with an operational span that is intended to be opened for the passage of waterway traffic.
*Drawspan* means the operational span of a drawbridge.
*Lowerable* means a non-structural vessel appurtenance that is or can be made flexible, hinged, collapsible, or telescopic so that it can be mechanically or manually lowered.
*Nonstructural* means that the item is not rigidly fixed to the vessel and can be relocated or altered.
*Not essential to navigation* means that a nonstructural vessel appurtenance, when in the lowered position, would not adversely affect the vessel's piloting, propulsion, control, or collision-avoidance capabilities.
*Public vessel* means a vessel that is owned and operated by the United States Government and is not engaged in commercial service, as defined in 46 U.S.C. 2101.
*Remotely operated drawbridge* means a drawbridge that is operated by remote control from a location away from the drawbridge.
*Removable span bridge* means a bridge that requires the complete removal of a span by means other than machinery installed on the bridge to open the bridge to navigation.
*Untended* means that there is no drawtender at the drawbridge.
[USCG-2001-10881, 71 FR 70307, Dec. 4, 2006]