pilot house, open to weather, containing a binnacle and voice tubes to allow the conning officer to direct the ship from a higher position during fair weather conditions. Larger warships may have navigation bridge, which is used for the actual conning of the ship, and a separate admiral's bridge can be provided in flagships, where the admiral can exercise control over the squadron of ships without interfering with the captain's command of the vessel. In older warships, a heavily armored conning tower was often provided, where the vital command staff could be located under protection to ensure that the ship could be commanded under fire. On a submarine, the bridge is the highest point on the conning tower, to provide for better visual navigation when on the surface. They became standard on United States Navy submarines after 1917, greatly improving the function of the vessels while at the surface. Configuration Modern advances in remote control equipment have seen progressive transfer of the actual control of the ship to the bridge. The wheel and throttles can be operated directly from the bridge, controlling often-unmanned machinery spaces. Aboard modern warships, navigational command comes from the bridge, whereas electronically directed weapon systems are usually controlled from an interior compartment. On a commercial vessel, the bridge will contain the equipment necessary to safely navigate a vessel on passage. Such equipment will vary with ship type, but generally includes a GPS navigation device, a Navtex receiver, an ECDIS or chart system, one or more radars, a communications system (including distress calling equipment), engine (telegraph) controls, a wheel/autopilot system, a magnetic compass (for redundancy and cross check capability) and light/sound signalling devices. Navigation station The navigation station of a ship may be located on the bridge or in a separate chart room, nearby. It includes a table sized for nautical charts where calculations of course and location are made. The navigator plots the course to be followed by the ship on these charts. Besides the desk and the navigation charts, the area contains navigational instruments that may include electronic equipment for a Global Positioning System receiver and chart display, fathometer, a compass, a marine chronometer, two-way radios, and radiotelephone, etc. Flying bridge A flying bridge, also known as "monkey island", is an open area on top of a surface ship that provides unobstructed views of the fore, aft, and the sides of a vessel. It serves