Merchants weapons

[phavoc]

For Britain, at least, the allure for a full scale implementation, didn't last long.

Being rather thirsty engines, especially at speed.

But it was also a solution looking at a problem that could have been resolved with enough light cruisers.

As to where you'd get said light cruisers, I tend to think this where keeping mothballed second and third classes come in.

The Royal Navy didn't have enough warships, even with 2nd and 3rd tier ships being used, to perform all the patrols required. What they did have was a number of liners that were available, and enough light guns and crews to arm them.

Not sure what you mean in reference to 'thirsty engines' - nearly all ships for the time were coal burners. England had coal, but had to import oil from Persian gulf. England had a number of older warships, and much to their chagrin, the U-boats found the slower capital ships to be great targets. They were too old and slow to be used with the more modern fleets, and when relegated to secondary duties they ended up getting sunk with a large loss of life (think Brittania). Or when one U-boat sank 3 cruisers sailing together in less than 2hs (HMS Aboukir, HMS Hogue, and HMS Cressy). Stupidity knows no bounds.

 

[Condottiere]

Passenger liners tended to optimize speed, so their engines consumed quite a lot of fuel.

Also, once they caught up with their prey, armament and protection was comparatively lacklustre, and even if on the level of a light cruiser, those had been designed with a view to combat damage containment, and had better fire control.

The question is always what enemy vessels they had expected to encounter, and counter, and for light cruiser on trade protection, it would be commerce raiders, which could be converted merchantmen, or enemy light cruisers detached for that role.

Anything larger would be hunted down by more heavier units.

As regards the cruiser massacre, later details indicate it was foreseeable, and smaller, faster units should have been assigned.

My estimation is that Fisher was correct, in getting rid of most of the older vessels, but they should been reactivated for trade protection, not to patrol European waters.

 

[phavoc]

Passenger liners tended to optimize speed, so their engines consumed quite a lot of fuel.

Also, once they caught up with their prey, armament and protection was comparatively lacklustre, and even if on the level of a light cruiser, those had been designed with a view to combat damage containment, and had better fire control.

The question is always what enemy vessels they had expected to encounter, and counter, and for light cruiser on trade protection, it would be commerce raiders, which could be converted merchantmen, or enemy light cruisers detached for that role.

Anything larger would be hunted down by more heavier units.

As regards the cruiser massacre, later details indicate it was foreseeable, and smaller, faster units should have been assigned.

My estimation is that Fisher was correct, in getting rid of most of the older vessels, but they should been reactivated for trade protection, not to patrol European waters.

AMC's would never want to deliberately seek out a confrontation with a real warship - the odds are heavily against them. Their best bet is surprise with torpedoes at close range. AMC guns simply weren't up to the job of sinking armored (and armed) cruisers.

Yes, liner's engines were generally optimized for speed, but they also carried large bunkerage's of coal which gave them sufficient range and time on station. They could extend that by reducing speed and reducing coal burn as needed. As far as I could tell coal consumption was never really a greater issue for them than it was for a regular warship.

AMC's did not expect to encounter German warships. They were there to impose the blockade on Germany, so they expected to encounter freighters - which their greater speed and tonnage would allow them to run down.

Yes, the sinking of the three cruisers was a combination of poor leadership (no effort to introduce zig-zag courses) and a general lack of escorts for the ships. Their sinking helped drive home that critical need for larger ships, though the RN was always short of hulls needed for it's very large area of operations and the duties it was expected to perform. That's what drove the introduction of Q-ships and AMC's.

There was really very little need for trade protection on Britain's trade routes after a certain period in the war. The combatants they needed to find had been sunk or retired to German ports. The German AMC's remained a threat for a time, but once they had been eliminated the RN didn't need to devote that many warships, and certainly not their better ones, to trade route protection. Blockade, shore bombardments and waiting around just in case the German High fleet sortied out became the main mission of the battle fleet. While that did tie up some of the cruise and destroyer fleet, many could be reassigned to blockade and escort duties. They resisted implementing non-troop convoys until well late into the war.

 

[Condottiere]

Armed Merchant Cruisers wouldn't, in normal circumstances, engage with actual warships, especially cruiser category and up.

But, with His Majesty's Ships Jervis Bay, and Rawalpindi, they went against, respectively, a pocket battleship, and two light ones.

With the Hochseeflotte contained within the North Sea, Goeben and Breslau in the Black Sea, and the heavy units of the Ostasiengeschwader hunted down and sunk by British battlecruisers, you could easily dispatch older units to guard the sealanes against converted German merchantmen, without worrying that they would come across heavyish cruisers.

I think that the Que ships were introduced more to trap an unseen enemy, specifically one that was submersible, rather than act as privateer hunters, since that would be a mission that wouldn't require much subterfuge.

As regards coal usage, what I read it was emphasized that fast liners weren't actually worth the consumption, and once it was clear that the Germans weren't going to waste their time and resources converting theirs to commerce raiders, anymore, it was less a chase, than establishing presence.

 

[phavoc]

Armed Merchant Cruisers wouldn't, in normal circumstances, engage with actual warships, especially cruiser category and up.

But, with His Majesty's Ships Jervis Bay, and Rawalpindi, they went against, respectively, a pocket battleship, and two light ones.

With the Hochseeflotte contained within the North Sea, Goeben and Breslau in the Black Sea, and the heavy units of the Ostasiengeschwader hunted down and sunk by British battlecruisers, you could easily dispatch older units to guard the sealanes against converted German merchantmen, without worrying that they would come across heavyish cruisers.

I think that the Que ships were introduced more to trap an unseen enemy, specifically one that was submersible, rather than act as privateer hunters, since that would be a mission that wouldn't require much subterfuge.

As regards coal usage, what I read it was emphasized that fast liners weren't actually worth the consumption, and once it was clear that the Germans weren't going to waste their time and resources converting theirs to commerce raiders, anymore, it was less a chase, than establishing presence.

Jervis Bay was doing escort duty for a small convoy, and it's Captain engaged to save as many convoy ships as possible. Jervis Bay couldn't outrun and it certainly did not outgun the Admiral Scheer. It's captain did the best he could for the circumstances, and arguably he did quite well by saving most of the convoy with his actions. Rawalpindi encountered a pair of battlecruisers and also could not run. In neither case did either ship seek out the Germans, they were happened upon BY the Germans and did what they could. Obviously they could have just surrendered, but that's not really the RN style.

Q-ships were, indeed, introduced to battle the unterseeboats of the Kriegsmarine. The idea being that a U-boat would surface and use it's deck gun rather than waste a torpedo.

It was Germany that suffered the most for a lack of coal than the UK did. Most fast liners were retained for troop transports. The ones converted to AMC's weren't the fastest, though they were more than fast enough to catch the much slower, and smaller, freighters. It was hulls that the UK needed to enforce the blockade and they didn't have enough.

 

[Condottiere]

That wasn't quite circumstantial, since pre Great War, the Royal Navy subsidized merchant shipping, so that weapon system hardpoints were prebuilt into the hulls.

I can't recall if any cannons were stored with the commercial vessels so prepared, and I do recall there was such a proposal, plus preplaced cannons at British colonial ports; I think that some bright spark at the Admiralty pointed out that stored weapons made sinking those commercial ships legal.

The Admiralty tended to be reactive to what they thought were potential foreign naval threats, that's why they wanted fast liners to deal with the enemy's conversions of such, without, I suspect, actually wargaming it out.

The real solution to any fast vessel that was commerce raiding were cruisers, and when heavier units started being designed (first class) armoured cruisers, eventually evolving into the Invincible class.

The actual mission was to sweep the trade lanes clear of the enemy armoured cruisers, and we'll assume any converted fast liners; any light cruisers, such as the Emden, or converted merchantmen, such as the Kormoran, should be able to be dealt with by any, cautious, cruiser or destroyer.

 

[phavoc]

That wasn't quite circumstantial, since pre Great War, the Royal Navy subsidized merchant shipping, so that weapon system hardpoints were prebuilt into the hulls.

I can't recall if any cannons were stored with the commercial vessels so prepared, and I do recall there was such a proposal, plus preplaced cannons at British colonial ports; I think that some bright spark at the Admiralty pointed out that stored weapons made sinking those commercial ships legal.

The Admiralty tended to be reactive to what they thought were potential foreign naval threats, that's why they wanted fast liners to deal with the enemy's conversions of such, without, I suspect, actually wargaming it out.

The real solution to any fast vessel that was commerce raiding were cruisers, and when heavier units started being designed (first class) armoured cruisers, eventually evolving into the Invincible class.

The actual mission was to sweep the trade lanes clear of the enemy armoured cruisers, and we'll assume any converted fast liners; any light cruisers, such as the Emden, or converted merchantmen, such as the Kormoran, should be able to be dealt with by any, cautious, cruiser or destroyer.

I am not aware of the RN paying for weapon mounts at the time of building a ship. I looked up what I could in my naval books and the closest I could find was a passage about the RN paying for guns, ammo and doing the training of merchantmen while the ship owners paid for the modifications to the ships. This was circa 1913 when conditions between UK and Germany were breaking down and they could not agree upon where auxiliary cruisers were to be armed. The UK said only in home ports, but the Germans argued that as long as it was done outside of neutral territory on the high seas it could be the same as doing it at home. With a much larger merchant marine and world wide interests its obvious one can see why the UK was pushing for such a thing.

In one instance the Germans removed the guns from the light cruiser Konigsberg. It actually carried a pair of 88mm guns meant to be used to arm any merchants that got captured. And at least one gun had been removed and used to arm a boat in East Africa.

For the most part the RN simply outnumbered and outbased German commerce raiders around the world. German raiders had no safe ports they could fight from with which to threaten RN shipping lanes and ships. However their actual efforts tied up a disproportionate amount of RN resources until the threats were mostly eliminated. Had the Germans been able to keep a few ships out there through the war the RN would have been forced to divert a lot more resources to dealing with them.

 

[Condottiere]

I think it's still going on: the Americans subsidizing partial costs of merchant ships that would be commandeered by the military, in the event of a war.

In the logic of both the shipping lines and the Admiralty, it made sense.

The shipping companies get free money for a bet that may never occur, and the Royal Navy gets an instant increase, for existing waterborne hulls, if they need it.

Actual war experience has modified these expectations.

Come to think of it, the Chinese are very enthusiastic builders of dual use hulls.

 

[phavoc]

I think it's still going on: the Americans subsidizing partial costs of merchant ships that would be commandeered by the military, in the event of a war.

In the logic of both the shipping lines and the Admiralty, it made sense.

The shipping companies get free money for a bet that may never occur, and the Royal Navy gets an instant increase, for existing waterborne hulls, if they need it.

Actual war experience has modified these expectations.

Come to think of it, the Chinese are very enthusiastic builders of dual use hulls.

Had to look that one up. You are referring to the U.S. Maritime Administration (MARAD) Maritime Security Program (MSP). It's mostly RO/RO and container ships that military needs to move equipment around the world to places. There are 60 ships listed, and from what I could find it would appear the heaviest armament they MIGHT carry is a CIWS system. Other than that a few have .50cals and small arms are available to crew.

Just about any ship can get a pintle-mount welded on and it has become an armed merchant ship. Kind of like the AMC's of WW1 / WW2 era - mostly temporary mounts with little protection for the team crewing the weapons.

A better analogue might be the Civil Reserve Air Fleet where they government pays for airliners to be built with reinforced flooring to carry heavier cargo's in the event they are needed to transport military goods. The aircraft don't get any other goodies like flare/chaff/radar threat warning receivers, but the owners do get some extra dollars just by being in the CRAF.

The US has so few US-flagged ships and it's domestic ship building industry is pretty anemic compared to China and it's desire to subsidize it's way to the forefront of the world's civil shipbuilding capacity. Them and South Korea.

 

[collins355]

Yes, and the Chinese are arming their merchants...

https://www.navalnews.com/naval-news/2025/12/container-ship-turned-missile-battery-spotted-in-china/

 

[Condottiere]

There is the modular approach.

 

[Sigtrygg]

Yes, and the Chinese are arming their merchants...

https://www.navalnews.com/naval-news/2025/12/container-ship-turned-missile-battery-spotted-in-china/

This makes sinking any and every container ship legal during war, as they are all now potentially enemy combatants.

The US did this years ago but refrained from equipping ships with the containers...

 

[phavoc]

This makes sinking any and every container ship legal during war, as they are all now potentially enemy combatants.

The US did this years ago but refrained from equipping ships with the containers...

The Brits converted the Atlantic Conveyor into a sort of armed merchant / auxiliary carrier when they embarked Harriers and helo's aboard. While they only transported the Harriers I don't see anything that may have stopped them from using it as a true carrier - though operationally it was certainly not designed for such operations and would have had many challenges. Up against someone who had no real defenses against it it could have made a formidable auxiliary enemy.

And lets not forget the submarine-stealing super tanker from The Spy Who Loved Me.

 

[Condottiere]

There was Her Majesty's Ship Ocean, built to commercial standards.

Difference, I'm told, besides cost, is damage control.

The Americans did convert a couple of tankers to Expeditionary Bases, afloat.