Video
Patreon 91: Flower class sloops: The most key ship of the 20th century?
Study Patreon 91: Flower class sloops: The most key ship of the 20th century?, a Dr. Alex Clarke video from 21 Dec 2023, with 59 time notes. Topics include Anti-Submarine Warfare, Conflict Management, Escort Warfare.
Time notes
- 8:00How wartime escorts became peacetime presence shipsChapter
Mass-produced Flower-class sloops outgrew their wartime purpose and became a model for persistent, affordable naval presence.
- 14:30Why the Royal Navy reused flower namesChapter
Flower names supplied a large naming pool, ready-made ship badges, and an identity around which a newly assembled crew could unite.
- 22:05Fishery protection teaches presence and restraintChapter
Small patrol commands teach officers to deter illegal activity, manage escalation, and achieve results without using disproportionate force.
- 25:07The best-timed naval visit is continuous presenceChapter
Regular, familiar naval presence can spot tension early and keep rivalry from becoming armed conflict.
- 35:07Fisher's efficiency reforms weakened routine presenceChapter
Fisher's efficiency drive removed many older station ships whose numbers, local knowledge, and fleet backing had made routine British presence credible.
- 40:33Presence ships need diplomatic facilities alongside weaponsNotable Point
A ship's flag and access to a larger fleet create influence, but hosting spaces determine whether its crew can turn a visit into useful engagement.
- 43:57Why battlecruiser visits led back to light-cruiser numbersChapter
Fisher expected spectacular battlecruiser calls to sustain influence between visits, but the Royal Navy still needed large light-cruiser numbers for regular engagement.
- 51:33Frequent small visits compound naval influenceNotable Point
A simple scoring example shows how repeated small-ship visits can retain more influence than one impressive annual appearance.
- 58:07QuestionDid the Battle of Coronel show that the Royal Navy's older global-presence ships were a flawed system?AnswerQ&A
No. The defeat is attributed chiefly to dispersal and failed reinforcement. HMS Defence might have deterred von Spee, while an Invincible-class battlecruiser would likely have reversed the balance.
- 1:01:53Media magnifies visits but cannot replace themNotable Point
Publicity can extend the reach and duration of a port visit, but it works as a multiplier for physical engagement rather than a substitute for ships on station.
- 1:03:00World War I exposed the need for purpose-built small escortsChapter
World War I found converted trawlers too small for every escort and minesweeping requirement, creating demand for stronger purpose-built small warships.
- 1:04:59QuestionIf the naval arms race had not occurred, would Britain's surviving pre-dreadnoughts have become presence ships?AnswerQ&A
A few probably would, with Lord Nelson and Agamemnon plausible distant-station ships, but not the whole older battle fleet.
- 1:05:23What navalized merchant construction actually meantNotable Point
The Flower hulls borrowed merchant practice for economy but retained naval strengthening where minesweeping and escort work demanded it.
- 1:08:11Five Flower batches produced 120 wartime escortsChapter
Successive minesweeping and anti-submarine batches gave Britain and France 120 Flower-family sloops, about 100 of which survived the war and immediate aftermath.
- 1:11:38Judge a sloop by its mission, not first-rate statusChapter
Flower-class armament was flexible but modest; effectiveness came from matching the ship to mines, submarines, escort support, and presence work.
- 1:16:36QuestionDid Flower-class sloops and other anti-submarine escorts use ramming tactics against submarines?AnswerQ&A
Yes. Ramming was part of anti-submarine doctrine and was attempted by dedicated escort vessels as well as by famous larger ships.
- 1:22:40Enterprise survived the postwar cruiser debate, Euphrates did notNotable Point
Treasury pressure shadowed HMS Enterprise's completion, while the sharper Royal Navy debate concerned the cancelled third E-class cruiser, HMS Euphrates.
- 1:24:53Flower-class sloops as task-group security shipsNotable Point
The sloop adds specialized protection against submarines and mines rather than acting as a fleet picket or principal surface fighter.
- 1:28:30QuestionDid sloop deck guns fire on the upward roll, and how was the firing moment chosen?AnswerQ&A
The choice depended on range and aim point: the roll could add elevation for long shots or help point downward at close targets, while trained crews relied on the guns' rapid rate of fire.
- 1:32:34The World War I Flower pattern shaped later escortsChapter
The Flower sloops established a durable small-escort pattern later refined into interwar sloops, wartime corvettes, escort destroyers, and frigates.
- 1:35:12QuestionDid any World War I Flower-class sloops remain in service during World War II?AnswerQ&A
Yes. About two did, including HMS Foxglove, which survived severe 1940 bomb damage and continued in support duties rather than returning to front-line escort work.
- 1:38:54The modern HMS Enterprise left service in 2023Notable Point
A live correction notes that the Echo-class survey ship HMS Enterprise had decommissioned in March 2023, following sister HMS Echo in 2022.
- 1:40:41HMS President preserves a Flower-class survivorNotable Point
The former HMS Saxifrage, later HMS President, is presented as the likely last surviving physical example of the World War I Flower-family sloops.
- 1:42:36Bomb-hit location shaped small-warship survivalNotable Point
A bomb amidships could destroy machinery spaces, while comparable hits near the ends of a sloop or destroyer left more structure available to contain damage.
- 1:43:33HQS Wellington makes preserved sloop history tangibleNotable Point
The white-hulled HQS Wellington offered a preserved small-warship setting where students could study naval design and service life directly.
- 1:44:24Escort mass production demonstrated industrial intentChapter
Building and crewing roughly 120 escorts showed Germany that Britain could replace losses, protect trade, and mobilize maritime industry at scale.
- 1:50:03Interwar sloops helped build Dominion naviesChapter
HMS Veronica shows how inexpensive station sloops extended British presence while helping Dominion navies such as New Zealand's build local capability.
- 1:54:20QuestionHow senior were the officers who usually commanded Flower-class sloops?AnswerQ&A
They were generally lieutenant commanders or commanders, making sloops valuable early independent-command appointments for future cruiser officers and warfare specialists.
- 1:56:10QuestionWhich famous officers came out of the Royal Navy's sloop service?AnswerQ&A
Frederic John Walker is the leading example, emerging from a sloop-based anti-submarine specialism before commanding Stork and Starling.
- 2:03:55QuestionHow many former naval officers went into diplomatic service, and why were they recruited?AnswerQ&A
A considerable number did because they already spoke relevant languages, understood overseas regions, and knew how to work with other officials.
- 2:04:13QuestionIf Britain had maintained and distributed sloop production through the interwar years, how would that have changed World War II?AnswerQ&A
A steady program could have supplied a large prewar escort force, reduced emergency construction, strengthened early convoy defense, and expanded the industrial and personnel base available for wartime growth.
- 2:08:47HMIS Pansy and the interwar sloop revivalChapter
A reused World War I Flower hull and the renewed British building program show how interwar sloop capacity survived and then grew in batches.
- 2:12:08Eight sloops a year could reshape the early U-boat warChapter
A steady eight-ship annual program could reduce emergency escort construction and make early U-boat losses damage Germany's later training cadre.
- 2:17:40QuestionWould building many more interwar sloops have changed destroyer development?AnswerQ&A
Destroyers would develop much as they did, but a larger sloop program could accelerate dual-purpose guns and expand turbine capacity available to both classes in wartime.
- 2:18:53QuestionDoes the Perisher course remove the need for cheaper submarines as command-development platforms?AnswerQ&A
No. Perisher is an excellent selection course, but successful officers would still benefit from commanding an SSK before taking responsibility for an SSN.
- 2:20:41HMS Folkestone at the Singtao incidentChapter
A sloop accompanied HMS Birmingham to recover SS Vincent de Paul, adding presence and tactical flexibility without making the force look needlessly escalatory.
- 2:34:53River-class OPVs as modern presence squadronsChapter
Modern patrol vessels fill the low-cost, persistent role once served by sloops, but useful coverage requires several ships at each important station.
- 2:36:37QuestionWhy did Royal Navy sloops lack torpedo armament?AnswerQ&A
Because they were optimized as adaptable low-speed escorts and presence ships; torpedoes and destroyer speed would spend resources on a surface-strike role outside their purpose.
- 2:43:22QuestionWhy not replace the River class's 30 mm gun with a close-in weapon system or otherwise up-gun the ships?AnswerQ&A
Because extra weapons make the ship costlier and more complex while encouraging it to be sent into threats meant for frigates or destroyers; modest sensors, electronic warfare, drones, and a 40 mm gun better fit the OPV mission.
- 2:50:35Sandown minehunters continued the minesweeping-sloop roleNotable Point
Sandown-class minehunters are functional sloops because mine warfare had long been one of the type's defining missions.
- 2:50:52Threat tiers keep patrol ships out of destroyer missionsNotable Point
A layered fleet should send a River, Type 31, Type 26, or Type 45 according to the threat instead of making every patrol ship imitate a frigate.
- 2:55:15River Batch 2 trades heavy weapons for endurance and peopleNotable Point
Speed, roughly month-long endurance, fast boats, a helicopter-capable deck, and space for up to 50 embarked personnel make Batch 2 Rivers useful for persistent security work.
- 2:58:08QuestionHow would a modern uncrewed Flower-class support ship be configured, and could it carry drones?AnswerQ&A
A River-class-derived hull could retain a flight deck, basic maintenance accommodation, autonomous controls, limited guns and VLS, but drone handling would still need substantial automation or human intervention.
- 2:59:29Why 40 mm leaves room for better ammunitionNotable Point
The extra volume inside a 40 mm shell makes advanced ammunition easier and more economical to develop than comparable 30 mm rounds.
- 3:02:15A 57 mm gun changes the patrol-ship cost equationNotable Point
A 57 mm gun offers a real capability increase over 40 mm, but its larger cost jump makes an OPV look more like a cheap frigate without delivering Type 31 capability.
- 3:06:26QuestionWhat gun caliber is too large for an offshore patrol vessel?AnswerQ&A
It depends on the navy: a 76 mm gun fits Thailand's fleet commonality and force structure, while 40 mm is the more proportionate British upgrade from 30 mm.
- 3:12:22Presence ships need austere, off-the-shelf systemsNotable Point
An OPV gains more from standard, easily maintained equipment than from bespoke high technology that demands specialist support in distant ports.
- 3:13:34QuestionWhy are so many NATO offshore patrol vessels armed with 20 mm guns?AnswerQ&A
Because 20 mm is cheap and often proportionate to the patrol vessel's size, operating area, and expected threats.
- 3:14:08Public access favours simple, securable ship systemsNotable Point
Weapons and equipment on a diplomatic presence ship should be easy to secure, inspect, and restore when visitors come aboard.
- 3:14:47StanFlex pays off only as a fleet-wide systemNotable Point
Danish modularity makes the Knud Rasmussen-class patrol vessels a compelling modern sloop model, but another navy must fund modules, support, and common interfaces across more than one OPV class.
- 3:18:22Retaining Type 23s beats converting Rivers for the frigate gapNotable Point
If Type 31s are late, extending suitable Type 23s preserves real frigate capability more effectively than taking River OPVs offline for complex upgrades.
- 3:24:33Reserve ships protect a fleet against long-war attritionChapter
Small fleets are brittle when refits overrun or worn ships fail, making reserve hulls and low-end ships important to sustained readiness.
- 3:31:08Nuclear stalemate makes limited-war control more importantNotable Point
If both superpowers know nuclear use means mutual loss, rivalry continues below that threshold and conventional escalation must be managed carefully.
- 3:32:39QuestionCan a River-class patrol vessel receive supplies from a Chinook helicopter?AnswerQ&A
Merlin capability is clear, but possible Chinook testing on HMS Clyde is recalled without confirmation.
- 3:33:49Long wars expose vertical-launch replenishment limitsNotable Point
Vertical-launch systems designed on the assumption that their magazines would not need reloading become a logistical constraint once a conflict lasts.
- 3:35:37QuestionCould an enlarged River-class offshore patrol vessel be turned into a corvette?AnswerQ&A
Yes. BAE's Avenger proposal did so for the Type 31 competition, but it offered too little capability beyond the River family compared with the selected Arrowhead frigate design.
- 3:39:27More modest hulls improve force generationChapter
Twelve simpler ships can sustain more deployments and absorb refit failures better than six more powerful ships bought for the same budget.
- 3:44:58QuestionHow could Britain add submarine force multipliers around its SSNs and ballistic-missile boats?AnswerQ&A
It could add cheaper SSKs, or build two extra Dreadnought-family hulls configured as SSGNs with the potential to backfill the ballistic-missile role when required.
- 3:48:29Crew growth must precede faster shipbuildingNotable Point
Turning on the shipyard pipeline too quickly creates empty hulls unless recruitment and training expand early enough to provide crews when the ships commission.