Sixteen ships of the Royal Navy

Royal Navy

The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...

 have borne the name HMS Alert (or the variants Alerte and Alaart), while another was planned:
, a 8-gun cutter in service from 1753 to 1754., a 10-gun cutter launched at Dover in 1777, converted to a sloop in the same year, and captured in the Channel by the Junon

French frigate Junon (1778)

The Junon was a 32-gun Charmante class frigate of the French NavyShe took part in the Battle of Ushant under Admiral d'Orvilliers. She captured HMS Fox on 11 September 1778....

 in 1778; foundered December 1779 off the coast of America., a 10-gun cutter launched at Dover in 1778 and captured by the French ship Diligente in 1780; recaptured by ., a 14-gun brig-sloop launched at Dover in 1779 and sold 1792., a 4-gun schooner

Schooner

A schooner is a type of sailing vessel characterized by the use of fore-and-aft sails on two or more masts with the forward mast being no taller than the rear masts....

 purchased in 1790, wrecked in 1791, but possibly salved and broken up in 1799.

• HMS Alerte
  French brig Alerte (1787)
  The French brig Alerte was launched in 1787 and captured by the Royal Navy at Toulon in 1793. The British set her on fire when they evacuated Toulon later that year. After the French rebuilt her as Alerte, she served at the Battle of Aboukir Bay. The British recaptured her in 1799 and took her into...
  
  , a 14-gun brig-sloop captured from the French in 1793, retaken by the French after being burnt to the waterline that same year and rebuilt by them, captured by in 1799, renamed HMS Minorca and sold in 1802., a 16-gun sloop launched at Rotherhithe in 1793 and captured by the French Unité in 1794 off the coast of Ireland; wrecked later that year after action with and ., a 8-gun brig-sloop launched at Bombay in 1795., previously the collier Oxford, purchased in 1804 and captured by the USS Essex
  USS Essex (1799)
  The first USS Essex of the United States Navy was a 36-gun or 32-gun sailing frigate that participated in the Quasi-War with France, the First Barbary War, and in the War of 1812, during which she was captured by the British in 1814 and served as HMS Essex until sold at public auction on 6 June...
  
   in 1812; remained in US service until 1829., a 16-gun Danish sloop captured in 1807 and retaken by the Danes in 1809. She was to be named Cassandra., a Cruizer-class
  Cruizer class brig-sloop
  The Cruizer class was an 18-gun class of brig-sloops of the Royal Navy. Brig-sloops were the same as ship-sloops except for their rigging...
  
   brig-sloop, launched in 1813 and sold in 1832., a 8-gun packet-brig launched in 1835 at Rotherhithe and broken up in 1835., a 8-gun brig, previously a slaver
  Slave ship
  Slave ships were large cargo ships specially converted for the purpose of transporting slaves, especially newly purchased African slaves to Americas....
  
  , captured in 1848 and sold 1850., a wooden Cruizer-class
  Cruizer class sloop
  The Cruizer class was a class of 17-gun wooden screw sloops built for the Royal Navy between 1852 and 1856, comprising six vessels.-Design:...
  
   screw sloop launched in 1856 at Pembroke Dock. She was converted for Arctic exploration in 1874, reached 82°N in the expedition of 1876, worked as a survey vessel, and was loaned to the US Navy and the Canadian Government. She was laid up in 1884 and sold., an Alert-class sloop
  Alert class sloop
  The Alert class was a two-ship class of 6-gun screw steel sloops built for the Royal Navy in 1894.-Design:Alert and Torch were constructed of steel to a design by William White, the Royal Navy Director of Naval Construction...
  
   launched in 1894 at Sheerness. She was lent to the civil authority at Basra in 1906, and sold to them in 1926 for use as a pilot vessel. She was broken up in 1949.
• Alert was an Algerine-class
  Algerine class minesweeper
  The Algerine-class was a class of minesweepers of the Royal Navy and the Commonwealth. 110 ships of the class were launched between 1942 and 1944 and served in World War II....
  
   minesweeper
  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:...
  
  , renamed HMS Acute in 1941 before being launched in 1942., a Bay-class
  Bay class frigate
  The Bay class was a class of 26 anti-aircraft frigates built for the Royal Navy under the 1943 War Emergency Programme during World War II...
  
   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"...
  
   launched in 1945, originally Dundrum Bay and Loch Scamadale. She was sold in 1971.

In addition, the Royal Navy used several hired armed vessels

Hired armed vessels

right|thumb|250px|Armed cutter, etching in the [[National Maritime Museum]], [[Greenwich]]During the eighteenth and nineteenth centuries the Royal Navy made use of a considerable number of hired armed vessels...

 with the name Alert, including several cutters Alert and a lugger

Lugger

A lugger is a class of boats, widely used as traditional fishing boats, particularly off the coasts of France, Scotland and England. It is a small sailing vessel with lugsails set on two or more masts and perhaps lug topsails.-Defining the rig:...

 Alert.