In some countries, frigate and patrol ship are two relatively similar ship types. Not only are their displacements relatively close, but they also have certain overlaps in combat performance. However, in essence, there is still a big difference between escort and patrol ships.
British Navy "River" class patrol ship
Patrol ship is a surface combat ship located below the frigate in Navy ship , also known as square light frigate, sometimes also known as frigate , gunboats, and gunboats. Patrol ships are mainly used for daily patrol and combat support in offshore defense, and can also be used to perform various tasks such as patrol alert, anti-submarine and anti-ship, mine-sweeping and air defense, and subsequent private rescue intelligence collection. The specific functions depend on the specific equipment design.
British Navy "Duke" class frigate
There are many international standards for the classification of patrol ships. The most typical classification standard believes that the displacement of light frigates is between 1,000 and 2,500 tons and the speed is above 25 knots. They are generally fighting in offshore waters and do not have the ability to operate from oceans. Modern patrol ships are equipped with rapid-fire automatic cannons, missiles, , deep-water bombs, , sonar, , radar, torpedo , infrared detection and other facilities. The hull size and design characteristics are also very similar to the coastal patrol boat, , but they are higher speed, stronger firepower and greater endurance than the latter. Some patrol ships even have the capability of carrying helicopters.
US Coast Guard "Hamilton" class patrol ship
At present, the US Coast Guard, Japan Coast Guard , South Korean Maritime Police Department , Russian Border Defense Forces and other coast guard forces with ocean-going activities are all equipped with large patrol ships, and the ships are equipped with machine cannon and large caliber naval gun (some are equipped with helicopters). Among them, some patrol ships owned by the Russian Border Defense Force are transformed from retired Russian Navy ships, and military-regulated equipment such as torpedoes and missiles have been removed.
Brunei Navy "Darutakwa" patrol ship
Because the patrol ship has the advantages of low cost, simple operation and maintenance, few crew members and strong combat capabilities, it is favored by the navies of small and medium-sized countries that are unable to build large and medium-sized surface ship .
