accommodation) can be forward, midship or aft. Motorised winches, electronic navigation and sonar systems are usually installed. Fishing equipment varies in sophistication depending on the size of the vessel and the technology used. Design features for modern fishing trawlers vary substantially, as many national maritime jurisdictions do not impose compulsory vessel inspection standards for smaller commercial fishing vessels. Mechanised hauling Mechanised hauling devices are used on modern trawlers. Trawl winches, such as Gilson winches, net drums and other auxiliary winches are installed on deck to control the towing warps (trawling wires) and store them when not in use. Electronics Modern trawlers make extensive use of contemporary electronics, including navigation and communication equipment, fish detection devices, and equipment to control and monitor gear. Just which equipment will be installed depends on the size and type of the trawler. Much of this equipment can be controlled from the wheelhouse or bridge. Smaller trawlers have wheelhouses, where electronic equipment for navigation, communications, fish detection and trawl sensors are typically arranged about the skipper's chair. Larger vessels have a bridge, with a command console at the centre and a further co-pilot chair. Modern consoles display all the key information on an integrated display. Less frequently used sensors and monitors may be mounted on the deckhead. Navigational instruments, such as an autopilot and GPS, are used for manoeuvring the vessel in harbour and at sea. Radar can be used, for example, when pair trawling to keep the correct distance between the two vessels. Communication instruments range from basic radio devices to maritime distress systems and EPIRBs, as well as devices for communicating with the crew. Fish detection devices, such as echosounders and sonar, are used to locate fish. During trawling operations, a range of trawl sensors may be used to assist with controlling and monitoring gear. These are often referred to as "trawl monitoring systems" or "net mensuration systems". net sounders (trawl eyes) give information about the concentration of fish around the opening to the trawl, as well as the clearances around the opening and the bottom of the trawl catch sensors give information about the rate at which the cod end is filling. symmetry sensors give information about the optimal geometry of the trawls. tension sensors give information about how much tension is in the warps and sweeps. Fish storage and processing Modern trawlers store the fish they catch in some form of chilled