WI: Pollen system adopted for director firing in the RN?

Saphroneth

Banned
The fire control system adopted by the Royal Navy in the late 1900s and early 1910s, the Dreyer system, allowed for firing by ships steaming in a straight line against an enemy ship at short to medium ranges.

But the alternative system offered by Pollen would have allowed longer ranged accurate fire, as well as fire by ships manoeuvering at speed (as it incorporated variable motion of own-ship-course).

What would have happened had this been adopted - assuming of course that WW1 goes mostly as OTL, the two major potential PoDs are the Dardanelles operation (where ships with the Pollen system would have been better able to attack the Dardanelles fortifications despite evasive manoeuvres) and Jutland.

So - what could the results be?
 
The fire control system adopted by the Royal Navy in the late 1900s and early 1910s, the Dreyer system, allowed for firing by ships steaming in a straight line against an enemy ship at short to medium ranges.

But the alternative system offered by Pollen would have allowed longer ranged accurate fire, as well as fire by ships manoeuvering at speed (as it incorporated variable motion of own-ship-course).

What would have happened had this been adopted - assuming of course that WW1 goes mostly as OTL, the two major potential PoDs are the Dardanelles operation (where ships with the Pollen system would have been better able to attack the Dardanelles fortifications despite evasive manoeuvres) and Jutland.

So - what could the results be?

At a guess, I don't think the Dardanelles would have changed that much. The reason the British called it off was the mining of three battleships. They might have inflicted more damagew on the forts, but there were a lot of them. This is unfortunate, because a better British result here might well favorably affect the war by getting more supplies to the Russians.

I would expect more effect from this improvement at Jutland, but the strategic effects are less. If the British sank 5 German battleships or battlecruisers at Jutland, does it make much difference strategically? The German fleet will still go into port and stay there, which was the OTL result.

It might even have an adverse effect on the war. The Germans could decide their fleet is useless, except as a "Fleet in being" and reduce the crews to caretaker levels (say 100 per BB/BC and 50 for smaller ships) and send the rest to retrain as infantry. That should provide another couple of divisions, wiothout making it obvious that the High Seas Fleet has been neutered.
 
... the two major potential PoDs are the Dardanelles operation (where ships with the Pollen system would have been better able to attack the Dardanelles fortifications despite evasive manoeuvres)...
I'd broadly agree with Trevayne and say that whilst they might do a bit more damage to the fortifications it probably wouldn't be enough to change the outcome. If you want the Dardanelles Campaign to go more successfully I would suggest that you need to advance the development of the paravane/Oropesa to help deal with the minefields.
 

hipper

Banned
The fire control system adopted by the Royal Navy in the late 1900s and early 1910s, the Dreyer system, allowed for firing by ships steaming in a straight line against an enemy ship at short to medium ranges.

But the alternative system offered by Pollen would have allowed longer ranged accurate fire, as well as fire by ships manoeuvering at speed (as it incorporated variable motion of own-ship-course).

What would have happened had this been adopted - assuming of course that WW1 goes mostly as OTL, the two major potential PoDs are the Dardanelles operation (where ships with the Pollen system would have been better able to attack the Dardanelles fortifications despite evasive manoeuvres) and Jutland.

So - what could the results be?

The Pollen system did not allow longer ranged accurate fire control compared to
The Dreyer table. It could only take ranges from one (high quality) rangefinder
The Dreyer table could take multiple ranges from multiple sources. It's architecture was more open and allowed for tinkering by Gunnery officers.

There is a quite nice description at dreadnoughtproject.org. but the best source is John Brooks book "Dreadnaught Gunnery and the battle of Jutland"

The PHD it's based on is available on the Internet.

Regards

hipper
 
The Dryer table can sometime seem inferior to the Pollen system. However from what I've read in Brooks' book is that it was more robust and could more easily be fixed using the resources of the ship. Pollen's system comes across as a bit more fragile and less suited to use aboard a warship in action.

Does appear that the belief in the Pollen system being superior comes from Pollen himself who felt he had been cheated by the Admiralty in some way. Dryer, OTOH, was a serving officer so could not at the time respond publicly.
I would also guess that suggesting that the RN had the wrong fire control equipment was easier than admitting that gunnery training in some parts of the fleet was deficient.
 
The Battleships of the Grand Fleet didnt seem to hit the Germans at Jutland any less often than the Germans hit back. It was the Battle Cruiser Fleets appalling gunnery that leads people to think the RN couldnt hit a barn door even if they were inside the barn.
 
DK Brown suggests the Dreyer "should have been adequate for battleships which were likely to fight on near-parallel courses with a slow rate of change of range": however, he thinks the battlecruisers might have benefitted from the Pollen gear. It seems more plausible that if they were going to try a new system they'd bring it in experimentally, and the battlecruisers might have been a good test platform. Their battles were likely to be more fluid and dynamic, which the Pollen was better at dealing with; they were intended to fight cruisers, so would have been knocked around less if the system was fragile; and a new system could hardly have made their gunnery any worse.

Presumably, though, there were a lot of other steps that could have been taken to improve gunnery- shifting spotting tops out of the plume of smoke from the engines, abandoning sighting hoods from the start, etc.- before you go to the length of buying a new director. Also worth remembering that the best gunnery in the world wouldn't have compensated for the deficiencies of the shells at Jutland, or the myriad inefficiencies at the Dardanelles.
 
Presumably, though, there were a lot of other steps that could have been taken to improve gunnery- shifting spotting tops out of the plume of smoke from the engines, abandoning sighting hoods from the start, etc.- before you go to the length of buying a new director.
Actually training the damn gunners in gunnery? That would have more impact, IMHO, than any change in equipment with the possible exception of armour piercing shells that actually penetrate armour.
 
Actually training the damn gunners in gunnery? That would have more impact, IMHO, than any change in equipment with the possible exception of armour piercing shells that actually penetrate armour.
Partly a result of the lack of gunnery facilities for the battlecruisers, though: Rosyth at Edinburgh is a lot closer to people than Scapa Flow at Orkney. Training crews to pass ammunition and load more quickly is a low-impact substitute.
 
Partly a result of the lack of gunnery facilities for the battlecruisers, though: Rosyth at Edinburgh is a lot closer to people than Scapa Flow at Orkney. Training crews to pass ammunition and load more quickly is a low-impact substitute.
Which rather prompts the question of how ships based at Portsmouth, Plymouth and Chatham shot. They must have had more-or-less local ranges, and the constraints around the South Coast were (and are) at least as bad as those around the Firth of Forth.

I can't see any reason why similar ranges couldn't have been set up within easy steaming of Rosyth, had the time and resources been made available to do so.
 
I can't see any reason why similar ranges couldn't have been set up within easy steaming of Rosyth, had the time and resources been made available to do so.
I suspect it had something to do with this. Bear in mind that the Royal Navy had been operating out of Devonport, Portsmouth and Chatham for several hundred years, whereas the base at Rosyth dated from 1909. Furthermore, weather around Portland (where a lot of pre-war battle practice was held) was distinctly better than in the far North, which will have further impeded gunnery practice. The necessary ranges could certainly have been created with the right will: I'm just pointing out that it wasn't like the battlecruisers had perfect opportunities to practice and chose to ignore them.
 
Pollen system has got to be one of the worst names for a firing system.

It just BEGS for jokes like 'distribute randomly in the wind and hope one lands'.
 
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