Rating system of the Royal Navy

The rating system of the Royal Navy and its predecessors was used by the Royal Navy between the beginning of the 17th century and the middle of the 19th century to categorise sailing warships, initially classing them according to their assigned complement of men, and later according to the number of their carriage-mounted guns.

The rating system of the Royal Navy formally came to an end in the late 19th century by declaration of the Admiralty.

[1] The earliest categorisation of Royal Navy ships dates to the reign of King Henry VIII.

Henry's Navy consisted of 58 ships, and in 1546 the Anthony Roll divided them into four groups: 'ships, galliasses,[Note 1] pinnaces, and row barges.'

"[2]: 128 [q 1] The formal system of dividing up the Navy's combatant warships into a number or groups or "rates", however, only originated in the very early part of the Stuart era, with the first lists of such categorisation appearing around 1604.

In 1626, a table drawn up by Charles I used the term rates for the first time in a classification scheme connected with the Navy.

No specific connection with the size of the ship or number of armaments aboard was given in this 1626 table, and as far as is known, this was related exclusively to seaman pay grades.

[1] Samuel Pepys, then Secretary to the Admiralty, revised the structure in 1677 and laid it down as a "solemn, universal and unalterable" classification.

Pepys's original classification was updated by further definitions in 1714, 1721, 1760, 1782, 1801 and 1817, the last being the most severe, as it provided for including in the count of guns the carronades that had previously been excluded.

The largest third rates, those of 80 guns, were likewise three-deckers from the 1690s until the early 1750s, but both before this period and subsequent to it, 80-gun ships were built as two-deckers.

These vessels, despite their small size and minimal armament, were often classed as second or third rate ships, appropriate for the seniority of the captain.

The smaller fourth rates, of about 50 or 60 guns on two decks, were ships-of-the-line until 1756, when it was felt that such 50-gun ships were now too small for pitched battles.

The Navy did retain some fourth rates for convoy escort, or as flagships on far-flung stations; it also converted some East Indiamen to that role.

These were too small to be formally counted as frigates (although colloquially often grouped with them), but still required a post-captain (i.e. an officer holding the substantive rank of captain) as their commander.

The larger of the unrated vessels were generally all called sloops, but that nomenclature is quite confusing for unrated vessels, especially when dealing with the finer points of "ship-sloop", "brig-sloop", "sloop-of-war" (which really just meant the same in naval parlance as "sloop") or even "corvette" (the last a French term that the British Navy did not use until the 1840s).

Technically the category of "sloop-of-war" included any unrated combatant vessel—in theory, the term even extended to bomb vessels and fire ships.

During the Napoleonic Wars, the Royal Navy increased the number of sloops in service by some 400% as it found that it needed vast numbers of these small vessels for escorting convoys (as in any war, the introduction of convoys created a huge need for escort vessels), combating privateers, and themselves taking prizes.

The count did not include smaller (and basically anti-personnel) weapons such as swivel-mounted guns ("swivels"), which fired half-pound projectiles, or small arms.

By the Napoleonic Wars there was no exact correlation between formal gun rating and the actual number of cannons any individual vessel might carry.

One therefore must distinguish between the established armament of a vessel (which rarely altered) and the actual guns carried, which might change quite frequently for a variety of reasons: guns might be lost overboard during a storm, be jettisoned to speed the ship during a chase, or explode in service and become useless; they might also be stowed in the hold to allow the carriage of troops, or, for a small vessel such as HMS Ballahoo, to lower the centre of gravity and thus improve stability in bad weather.

[5] The recommendation from the Board of Admiralty to the Prince Regent was dated 25 November 1816, but the Order in Council establishing the new ratings was issued in February 1817.

From that date, the first rate comprised all ships carrying 110 guns and upwards, or the complement of which consisted of 1,000 men or more.

The third rate included all the rest of HM's royal yachts and "all such vessels as may bear the flag of pendant of any Admiral Superintendent or Captain Superintendent of one of HM's Dockyards", and otherwise comprised all ships carrying at most 80 guns but not less than 60 guns, or the complements of which were under 800 but not less than 600 men.

Through the early modern period, the term "ship" referred to a vessel that carried square sails on three masts.

For instance, when the commanding officer of a gun-brig or even a cutter was a lieutenant with the status of master-and-commander, the custom was to recategorise the vessel as a sloop.

For instance, when Pitt Burnaby Greene, the commanding officer of Bonne Citoyenne in 1811, received his promotion to post-captain, the Navy reclassed the sloop as a post ship.

As of 1905, ships of the United States Navy were by law divided into classes called rates.