- There are six rating articles (1st, 2nd, 3rd, 4th, 5th, 6th) in the rating system of the Royal Navy.
The rating system of the Royal Navy was used between the 1670s and early 19th century to categorise sailing warships of the Royal Navy of its power to stand in a line of battle based on the number of guns. Cannons (large, smooth-bored, muzzle-loading guns) were counted, but not carronades (short guns which were half the weight of equivalent long guns), although rated ships could carry up to twelve 24 or 32-pounder carronades. It must be said that during the Napoleonic Wars the correlation between formal gun rating and actual number of long guns or carronades carried by any individual ship was theoretical at best.
When first established, first-rates were ships of exactly 100 guns, second-rates 90 guns, third-rates 70 guns, and fourth-rates 54–60 guns. As time passed, and different ships were built with greater or fewer numbers of guns, the term was expanded to include the ranges listed below.
Although the rating system was only used by the Royal Navy, British authors might still use "first-rate" when referring to the largest ships of other nations or "third-rate" to speak of a French 74. By the end of the 18th century, the rating system had mostly fallen out of common use, ships of the line usually being characterized directly by their nominal number of guns, the numbers even being used as the name of the type, as in "a squadron of three 74s".
The rating system did not handle ships smaller than the sixth rate, the remainder simply being "unrated". The larger of the unrated vessels were generally called sloops (but be warned that nomenclature is quite confusing for unrated vessels, especially when dealing with the finer points of "brig", "sloop-of-war", "corvette" and "post-ship" and whether any particular vessel is one, the other, or several of these at once). Sixth-rate ships were generally useful as convoy escorts, for blockade duties and the carrying of dispatches; their small size made them a bit unsuited for the general cruising tasks the fifth-rate frigates did so well.
Rating system
- The number of crew on a first rate was increased by 25 when used as an Admiral's flagship, by 20 with a Vice Admiral and 15 with a Rear Admiral.
- Originally from http://www.cronab.demon.co.uk/gen1.htm, with the author's permission.
In 1817, the Royal Navy introduced a new rating system which included carronades in the count.
The rating system was again modified later based more on the size of the crew.
First-rates were the largest ships of the line, but tended to be slow and invariably expensive to operate. As a result, the few first-rates were typically reserved as commanding admirals' flagships.
A second-rate had lighter guns on their middle and upper decks.
Powerful and able to fight in the center of a line of battle, second-rates were sometimes criticised for being slow and hard to maneuver. Where a first-rate vessel was considered too expensive or vulnerable to risk, a second-rate often served as a flagship.
A third-rate ship of the line had two gun decks (thus the related term two-decker) and included the 74-gun ship, the most popular size of large ship for navies of several different nations. It was an easier ship to handle than a first or second rate ship, but still possessed enough firepower to potentially destroy any single opponent. It was also cheaper to operate.
A fourth-rate two-decker was considered too weak to stand in the line of battle. The few that remained were relegated to convoy escort, or as flagships on far-flung stations. Some exceptionally large frigates also belonged in the fourth rate.
A fifth-rate sailing frigate acted as a fast scout or an independent cruiser.
A sixth-rate frigate was the smallest frigate.
The term first-rate has passed into general usage, as an adjective used to mean something of the best or highest quality available.
Second-rate and Third-rate are also used as adjectives to mean that something is of inferior quality.
| 
