The F class escort ships were a class of fleet escorts (Ger:

German language

German is a West Germanic language, related to and classified alongside English and Dutch. With an estimated 90 – 98 million native speakers, German is one of the world's major languages and is the most widely-spoken first language in the European Union....

 Flottenbegleiter) used by the Kriegsmarine

Kriegsmarine

The Kriegsmarine was the name of the German Navy during the Nazi regime . It superseded the Kaiserliche Marine of World War I and the post-war Reichsmarine. The Kriegsmarine was one of three official branches of the Wehrmacht, the unified armed forces of Nazi Germany.The Kriegsmarine grew rapidly...

 during the Second World War. Ten ships were built in total, of a type roughly comparable to British frigate

Frigate

A frigate is any of several types of warship, the term having been used for ships of various sizes and roles over the last few centuries.In the 17th century, the term was used for any warship built for speed and maneuverability, the description often used being "frigate-built"...

s or American destroyer escort

Destroyer escort

A destroyer escort is the classification for a smaller, lightly armed warship designed to be used to escort convoys of merchant marine ships, primarily of the United States Merchant Marine in World War II. It is employed primarily for anti-submarine warfare, but also provides some protection...

s. They were the only such type of ship built by the Kriegsmarine. The ten ships were not given names, but were designated F 1 through F 10.

Construction

The ships were built by Germaniawerft

Friedrich Krupp Germaniawerft

Friedrich Krupp Germaniawerft was a German shipbuilding company, located in the harbour at Kiel, and one of the largest and most important builders of U-boats for the Kaiserliche Marine in World War I and the Kriegsmarine in World War II.-History:The company was founded in 1867 by Lloyd Foster, as...

 (F 1 - F 6), Kiel

Kiel

Kiel is the capital and most populous city in the northern German state of Schleswig-Holstein, with a population of 238,049 .Kiel is approximately north of Hamburg. Due to its geographic location in the north of Germany, the southeast of the Jutland peninsula, and the southwestern shore of the...

, Blohm & Voss (F 7, F 8) and Wilhelmshaven dockyard (F 9, F 10). They entered service between 1936 and 1939. The ships were originally conceived as fast fleet or convoy escort ships that could also perform anti-submarine

Anti-submarine warfare

Anti-submarine warfare is a branch of naval warfare that uses surface warships, aircraft, or other submarines to find, track and deter, damage or destroy enemy submarines....

 and minesweeping

Minesweeper (ship)

A minesweeper is a small naval warship designed to counter the threat posed by naval mines. Minesweepers generally detect then neutralize mines in advance of other naval operations.-History:...

 work. They were also used as a testbed class for a new high-pressure steam power plant intended for use in future destroyer

Destroyer

In naval terminology, a destroyer is a fast and maneuverable yet long-endurance warship intended to escort larger vessels in a fleet, convoy or battle group and defend them against smaller, powerful, short-range attackers. Destroyers, originally called torpedo-boat destroyers in 1892, evolved from...

s.

As a class, they were overloaded and over-engined, which contributed to severe hull stress and very poor sea-keeping characteristics; these flaws were partially remedied by extensive rebuilds between 1938 and 1940. The power plants likewise proved to be prone to frequent breakdowns, and most of the ships were removed from operational service during the later years of the war after machinery failures meant the ships spent more time in repair than in use.

With the exception of fleet service and convoy duties between 1939 and 1941, they spent most of the war in use as tenders or U-boat

U-boat

U-boat is the anglicized version of the German word U-Boot , itself an abbreviation of Unterseeboot , and refers to military submarines operated by Germany, particularly in World War I and World War II...

 training ships.

Ships

One ship, F 9, was sunk in December 1939 after being torpedoed by HMS Ursula

HMS Ursula (N59)

HMS Ursula was a British U class submarine, of the first group of that class, built by Vickers Armstrong, Barrow-in-Furness. She was laid down on 19 February 1937 and was commissioned on 20 December 1938....

. The others survived the war and were scrapped or sunk as target ships.