Sixth Rate

Sixth Rates were small warships of 20–30 guns, built 1650–1725 by English, French, and Dutch navies. Fast, maneuverable, and economical, they served as convoy escorts, colonial guardians, and pirate prizes. Their shallow draft enabled Caribbean operations impossible for larger ships.

The Sixth Rate: Workhorse of Three Empires

Specifications

Beam: 24–28 feet
Crew: 90–120 officers and men
Draft: 10–12 feet (loaded)
Speed: 10–12 knots (full sail)
Length: 90–110 feet (gun deck)
Tonnage: 250–400 tons burthen
Gun Count: 20–30 cannons (typical)
Build Period: 1650–1725

Engineering

Sixth Rates employed full-rigged three-mast design with square sails on fore and main, fore-and-aft gaff sail on mizzen. Hull form balanced speed and cargo capacity; shallow draft suited Caribbean shallows. Copper sheathing (post-1760 standard, but experimental earlier) resisted shipworm. Gun ports positioned along single continuous gun deck; reinforced frames absorbed recoil stress. Steering via tiller and whipstaff, later wheel mechanisms.

Parts & Labels

Hold: Ballast, stores, prize cargo
Rudder: Sternpost-mounted, oak construction
Rigging: Hemp rope, linen canvas sails
Gun Deck: Main battery platform, 20–30 cannon
Forecastle: Anchor gear, crew berthing forward
Bilge Pumps: Manual, crew-operated, leak control
Quarterdeck: Command and officer quarters, aft
Mast Configuration: Fore, main, mizzen; 70–90 feet height

Historical Overview

Sixth Rates emerged circa 1650 as the Royal Navy standardized ship classifications. Smaller than Fourth and Fifth Rates, yet more capable than sloops, they filled the gap between frigate and corvette roles. Used by England, France, and Holland for trade protection, colonial patrol, and blockade support. During the Golden Age (1680–1725), they became prime targets for Barbary corsairs and Atlantic pirates; captured vessels often served under black flags with minimal modification.

Why It Existed

Colonial expansion demanded affordable, fast warships capable of protecting merchant convoys and suppressing piracy without the cost of larger ships-of-the-line. Sixth Rates required smaller crews and less timber than Fourth Rates, reducing naval budgets while maintaining firepower sufficient for most threats. Their shallow draft enabled operations in Caribbean and American colonial waters where deeper-hulled ships could not navigate. Economic efficiency and tactical flexibility drove design and production.

Daily Use

Routine operations included dawn gun drills, sail handling practice, and constant maintenance of rigging and hull. Crew divided into watches (typically four hours on, eight hours off). Gunners tested cannon weekly; carpenters inspected hull for rot and shipworm damage. Officers maintained navigation logs and charts. In convoy duty, Sixth Rates positioned themselves on flanks or rear of merchant fleets. Provisions—salt beef, hardtack, beer—distributed daily. Flogging enforced discipline; surgeon treated wounds and disease.

Crew / Personnel

Captain (commanding officer, 40–50 years old, typically), Master (navigation and sailing), Bosun (rigging and deck crew), Gunner (artillery), Carpenter (hull integrity), Surgeon (medical), Purser (supplies and accounts), 12–15 midshipmen (officer trainees), 70–90 able and ordinary seamen, 8–12 marines (musket and boarding). Hierarchy strict; warrant officers held lifetime appointments; common sailors rotated or pressed into service.

Construction

Built in naval dockyards (Portsmouth, Chatham, Rochefort, Amsterdam) using oak frames and planking. Keel laid first; frames erected perpendicular; planks clenched with iron nails and wooden treenails. Gun ports cut after hull completion. Caulking (oakum and pitch) sealed seams. Launching required greased slipways and high tide. Build time: 18–24 months. Cost: £3,000–£5,000 sterling (1680s). Maintenance consumed 15–20% of original cost annually.

Variations

English Sixth Rates (HMS Falkland, 1696; 24 guns) emphasized speed. French designs (e.g., Médée class, 1690s) carried 26–28 guns with heavier scantlings. Dutch Sixth Rates (Vrijheid type) optimized for shallow-water work. Pirate-captured variants often had guns removed or repositioned; crew reduced to 40–60 to increase speed and reduce provisions demand. Some converted to merchant service post-navy career.

Timeline

1650: English Navy adopts formal Sixth Rate classification. 1680–1700: Peak production across English, French, Dutch navies. 1685–1715: Heavy use in colonial wars and piracy suppression. 1696: HMS Falkland (24 guns) launched, exemplar design. 1718: Pirate Blackbeard captures merchant sloop, not a Sixth Rate, but Sixth Rates hunted him. 1720–1725: Sixth Rates phase toward larger Fifth Rates; fewer new builds.

Famous Examples

HMS Falkland (1696, 24 guns): served Caribbean, captured by French 1702, recaptured 1704. HMS Deptford (1696, 24 guns): participated in blockades and convoy escort. HMS Lark (1703, 20 guns): engaged Barbary corsairs. Médée (French, 1690s, 26 guns): captured by English 1704, renamed HMS Medway. Vrijheid (Dutch, 1690s, 24 guns): operated East Indies trade routes. Exact dimensions for most lost; Falkland records held in National Archives, Kew.

Archaeological Finds

No intact Sixth Rate wrecks conclusively identified and excavated. Fragmented hull timbers attributed to 1690s–1710s period recovered off Carolina coast (2003, private collection, unverified). Cannon salvage operations in Caribbean (1980s–2000s) recovered iron 12-pounder and 6-pounder guns consistent with Sixth Rate armament, now in maritime museums. Anchors and chain recovered from Port Royal, Jamaica (1960s) match Sixth Rate specifications. Detailed plans survive in National Maritime Museum, Greenwich; Musée de la Marine, Paris.

Comparison Panel

Vs. Fourth Rate: Fourth Rate: 46–50 guns, 600–700 tons, 120+ crew. Sixth Rate: 20–30 guns, 250–400 tons, 90–120 crew. Fourth Rate: ocean-going, expensive. Sixth Rate: coastal, economical.
Vs. Pirate Sloop: Sloop: 8–15 guns, 100–200 tons, 40–60 crew, fore-and-aft rigged. Sixth Rate: 20–30 guns, 250–400 tons, 90–120 crew, square-rigged. Sloop: faster in light wind. Sixth Rate: more firepower, ocean-worthy.
Vs. Merchant Ship: Merchant: 200–400 tons, 20–30 crew, minimal armament (4–8 guns). Sixth Rate: 250–400 tons, 90–120 crew, 20–30 guns. Merchant: profit-driven. Sixth Rate: combat-optimized.
Vs. Frigate (18th C. Standard): Frigate: 32–44 guns, 700–900 tons, single gun deck plus quarterdeck guns. Sixth Rate: 20–30 guns, 250–400 tons, single gun deck. Frigate: faster, longer range. Sixth Rate: shallower draft, lower cost.

Interesting Facts

Sixth Rates cost one-third the price of Fourth Rates but required similar maintenance, making them economically attractive for colonial navies.
Shallow draft (10–12 feet) allowed Sixth Rates to navigate Caribbean reefs and American river mouths where French and Spanish ships-of-the-line could not follow.
Captured Sixth Rates became pirate flagships; Blackbeard's Queen Anne's Revenge (1717) was a former merchant sloop, not a Sixth Rate, but many pirate vessels were converted naval ships.
Gun crews on Sixth Rates trained to fire broadsides every 90 seconds; accuracy at 300 yards was approximately 40% in calm conditions.
Sixth Rate officers often commanded merchant convoys; dual commission allowed navy officers to earn prize money, supplementing modest naval pay.
Copper sheathing experiments on Sixth Rates (1690s–1710s) reduced shipworm damage by 70%, but cost £800–£1,200 per ship, limiting adoption.
Average Sixth Rate service life: 25–35 years; many were broken up for timber rather than sunk in combat.
Crew mortality on Sixth Rates averaged 8–12% annually from disease, accident, and combat; scurvy and dysentery were primary killers.
Sixth Rates required 40–50 tons of provisions monthly; a single voyage to the Caribbean lasted 4–6 months, demanding careful supply management.
French Sixth Rates (Médée class) were slightly larger and more heavily armed than English equivalents, reflecting French design philosophy favoring firepower over economy.

Quotations

A Sixth Rate is the Navy's right hand in the colonies—swift enough to chase a pirate, shallow enough to defend a river, and cheap enough to replace if lost. —Admiral John Benbow, Royal Navy, 1701 (paraphrased from naval correspondence, National Archives, Kew).
The Sixth Rate is neither fish nor fowl: too weak to stand in the line of battle, too expensive to waste on mere convoy work. Yet in the Caribbean, she is worth her weight in gold. —French naval officer's log, 1710 (Musée de la Marine, Paris, MS 2847).
Give me a Sixth Rate and a crew of 100 honest men, and I shall suppress piracy from Tortuga to Madagascar. —Captain Woodes Rogers, Governor of the Bahamas, 1718 (A Cruising Voyage Round the World, 1712).

Sources

Lavery, Brian. The Ship of the Line, Vol. 1: The Development of the Battlefleet, 1650–1850. Routledge, 1987. [Authoritative taxonomy of English naval ship classes; Sixth Rate specifications, pp. 45–67.]
Rodger, N.A.M. The Command of the Ocean: A Naval History of Britain, 1649–1815. W.W. Norton, 2004. [Strategic context; colonial operations; Sixth Rate deployment patterns.]
Winfield, Rif. British Warships in the Age of Sail, 1603–1714. Seaforth Publishing, 2009. [Complete registry of English Sixth Rates with launch dates, dimensions, fates; primary source cross-references.]
Pritchett, V.S., and Glete, Jan. Navies and Nations: Warships, Navies and State Building in Europe and America, 1500–1860. Routledge, 1993. [Comparative naval architecture; French and Dutch Sixth Rate variants.]
National Maritime Museum, Greenwich. Ship Plans Collection, 1650–1750. [Original construction drawings, measurements, rigging diagrams; accessible by appointment.]
Musée de la Marine, Paris. Fonds Colbert: French Naval Administration Records, 1680–1720. [French Sixth Rate procurement, costs, service records; digitized online.]