British Fire Control Systems at Jutland

The Battle of Jutland continues to be an interesting and controversial topic, in part because of technical arguments surrounding British gunnery and the effectiveness of the control of its fire.

This article is going to catalogue the equipment each British ship carried into battle and the conditions under which it was used. The overall impression I find in recording this is that strongly stated conclusions by naval historians who have not closely studied the technical function of fire control systems on the strengths and weaknesses in British gunnery are inappropriate.

A Heterogeneous Naval Battle

To take an informed position on the gunnery results of Jutland, one has to consider many factors. One mistake that can distort impressions taken when historians seek to analyse gunnery effectiveness in this era is to treat the British and German forces as monolithic fleets possessing uniform equipment as well as degree and freshness of gunnery drill, fighting each other en masse under tactical and environmental conditions offering neither force an advantage. Assuming such conditions prevailed can only serve as the basis of a flawed understanding of everything that followed.

Let's consider equipment first. While the British ships generally relied on director firing at ranges and deflections calculated on Dreyer Fire Control Tables informed from the visual estimates of range and bearing obtained by coincidence range finders and similar instruments, not every ship used its director all the time, some few ships lacked a director, some ships lacked a Dreyer table, others used different types of Dreyer table, and a great many reported that their rangefinders did not really work very well in the necessary conditions. The British did have an advanced suite of apparatus for controlling their guns, but it was a general scheme — not a strictly standardised one.

As to training, the plurality of battle data the war produced where ships could be seen methodically applying their equipment, training and doctrine — the crucible, if you will — occurred during Jutland's "Run to the South", where the British Battle Cruiser Fleet's six battlecruisers with tardy, remote support from four super-dreadnoughts of the Fifth Battle Squadron engaged the five battlecruisers of the High Seas Fleet's Scouting Group. The British battlecruisers, while being the most battle experienced ships in the Grand Fleet, had the least secure anchorage and this offered them few opportunities to fire their guns in a live firing drill — exactly the type of drill that permitted all aspects of the fire control process to be practised and improved. By contrast, the rest of the Grand Fleet could conduct test firings with relative ease within the guarded confines of Scapa Flow, and the enemy had the Baltic in which to conduct battle practise without the threat of suffering a surprise attack.

As to the "en masse" aspect, it is vital to consider that the war seldom offered the two navies the opportunity to throw their entire "team" onto the field to exert their firepower in a test that evenly highlighted the average or mean of their capabilities. Rather, battles often pitted a small subset of one fleet against a subset of the other, and these engagements illustrate not the overall gunnery strength of the fleets, but only those of the ships engaged, with their specific equipment, and under the specific conditions of the engagement.

The final bias to consider is how the tactical position and prevailing environmental conditions dealt the various fighting formations at different phases of the battle a different hand of cards. John Brooks has illustrated how Vice-Admiral Beatty's command decisions imposed unnecessary burdens of smoke interference on his ships and denied them the full use of the numerous rangefinders they carried. Many have commented about the inequitable lighting that the opponents faced during both the Run to the South and when the battlefleets met, and certainly the fading day creates a difference in character between conditions during these two component engagements. It is foolish to consider them in an aggregate analysis without examining their differences.

Battle Conditions

Naturally, a navy has to fight (or decline to fight) under whatever conditions fate offers it, and the people who create a navy must answer for any deficiencies that arise out of whatever circumstances reveal them. It does not suffice to say, "Well, we never expected them to fight downwind of us!"

One argument about World War I fire control is particularly sensitive to the impact of the poor visibility that dominated much of Jutland's fighting: the controversy of Arthur Pollen's rejected Argo Aim Correction equipment versus the Frederic Dreyer's Fire Control Tables which the Royal Navy had chosen to adopt. Both systems were much more advanced than the system of control employed by the enemy, but the higher aspirations of both degraded sooner and more dramatically under sub-optimal visibility conditions than did the more to-the-point methods of the German fleet. However, when the virtues and faults of Argo and Dreyer solutions are compared under conditions where the input they are supplied becomes sparse and noisy as opposed to abundant and precise (or at least answering to Gaussian error patterns), it becomes clear that the differences between the two approaches become almost immaterial. This realisation makes the continued acrimony seem the moot fodder of partisans who have not really examined the problem of the tests fire control systems actually faced in the Great War.

Caveats and Sources

Airtight and detailed information on these particulars is thin. While there is good documentation overall, much is dated significantly distant from the battle, and this introduces the possibility that upgrades or alterations occurred between the battle and the document's creation regardless of which came first. Of course, the creators of most such documents were human, and some would even confess as much when pressed.

This page will have fuzzy edges and may contain errors. However, it should be substantially correct in aggregate.

The Run to the South

Ship	Dreyer Table	Director	FTP	9-ft R.F.s	15-ft R.F.s
Lion	III	yes	yes	4	0
Princess Royal	III	yes	yes	4	0
Queen Mary	II	yes	yes	6	0
Tiger	IV	yes	yes	7	0
New Zealand	none?	yes	yes	3	0
Indefatigable	none?	yes	yes	3	0
Barham	IV*	yes	yes	1	5
Valiant	IV*	yes	yes	1	5
Warspite	IV*	yes	yes	1	5
Malaya	IV*	yes	yes	1	5

Collecting the Forensic Data

Various calls from above were issued to ask subordinate commands to submit their best accounts of what had transpired during the battle. Gunnery details played a prominent part in the story. When replies were in hand, one thing seemed clear: rangetaking varied from poor to none at all, and spotting was also often problematic for many ships at critical junctures.

Vice-Admiral Beatty was quick on the mark, asking for a gunnery report from each of his battlecruisers and light cruiser squadrons on 7 June. The amount of detail in the reports submitted varied considerably, in part because not all ships had engaged in much gunnery. These reports did not appear in the Jutland Despatches, but some of them can be found in the Beatty Papers at the National Maritime Museum, specifically those for Indomitable, Inflexible, First L.C.S. and Third L.C.S.

On 24 September, Jellicoe asked his commanders to furnish more detail on their fire control during the battle, specifically asking that the paper range plots from the Dreyer tables be included with this report. Such material would comprise the most informative trove of forensic data by which we could evaluate British equipment and their use of it. However,

All ships did not furnish plots, transmission station records or other notes : reasons are explained in some of the following letters.

Ship	Submitted Plots	Summary
Revenge	No	No records maintained in action. No mention made of range cuts — only ranges on sights.
Benbow	No	From notes, Gunnery Officer Lieutenant Commander F. Elliott reported "obtained ranges on ship with 3 funnels" at 6.14. However, hits were obtained on a target an hour later after spotting down a full 1,600 yards. The implication of a 1,600 yard spotting correction is incredibly bad range data, if any is available at all.
Ajax	Yes	"Owing to the mist and smoke, this was all that could be obtained." "The trainer in Gun Control Tower had very great difficulty in seeing the object."
Erin	No	"only six ranges were taken altogether, at considerable intervals and no value could be obtained from them."
Monarch	No	No mention of even range on sights offered in report
Conqueror	Yes	"Very few ranges were taken."
Bellerophon	No	"very few ranges were obtained and though a small plot was made, the record has not been kept."
Malaya	Yes	Plot provided was from 4.00 to 4.33. "During the later stages of the action with the High Sea Fleet, ranges were few and isolated owing to low visibility." "No additional information is available."
Warspite	No	"neither the Dreyer Table chart nor any range and bearing records have been retained"
Princess Royal	No	No plot was submitted, but a detailed record of the action (profusely so, for some phases) from the fore T.S. is supplied, including timed relative bearings to the degree and timed ranges on the transmitters at 100 yard granularity.
Tiger	No	No plot was submitted, but a very detailed record of the action from the T.S. is supplied, including timed relative bearings to the degree and timed ranges on the transmitters at 100 yard granularity. Specific mention is made of rangefinder ranges as they compare to gun ranges, and of more than one rangefinder working
New Zealand	No	No plot was submitted, but a detailed record of the gun ranges is supplied at 50 yard granularity. Rangetaking is clearly occurring at the outset, but by 5.58 visibility seems too poor for spotting, let alone ranging.
Lion	Yes	Though this is not mentioned in the Despatches, Captain Chatfield submitted 2 range rolls and 3 bearing rolls on October 3rd.

Oddly, a few light cruisers were included in Jellicoe's appeal for data and offered the following in reply:

Ship	Summary
Calliope	Ranges are all divisible by 1,000 yards except one to 500 yards. No mention as to how obtained.
Constance	"all times, bearings and distances are approximate"
Inconstant	A total of 8 ranges only.
Falmouth	An outline of gun ranges and deflections of seven different target engagements from 6.07 to 8.38. After 6.30, all notes end with variations of "enemy lost to sight" despite ranges as low as 6,000 yards.
Birkenhead	Four separate impressions of worthless nature (e.g., "Smoke of enemy ships" bearing "North" at "10,000 yards (approx.)") recorded over 165 minutes.

The zeal for more information was intense, spurring Jellicoe to again ask on behalf of the Lords Commissioners of the Admiralty that ships should remit any last scintillae on 23 October, asking that replies avoid repeating data already offered. The request was specifically to provide:

• bearings and ranges to enemy capital ships from friendly battleships from 6.15 to 6.45 pm and 7.00 to 7.30 pm, and from the battlecruisers from 3.30 to 7.30 pm.
• range on sights, spotting corrections, and initial difference between plot range and gun range
• bearing plots where not already supplied

The appeal was to include cruisers and light cruisers.

The reports from British ships at the battle further outline the lack of range cut data.

• Marlborough at 6.15pm G.M.T. sighted an enemy battleship at a relatively close 10,000 yards (estimated) range. Even so, her gunnery officer reported that her "rangefinders could not get a range." Seven salvoes were fired anyway, and spotting and estimated ranges still (seemed to) provide sure hits on two of the salvoes. Subsequent target engagements did, in fact, seem to be supported by range cut data.
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What Went Wrong

Woven through the submitted responses above is frequent mention that few range cuts were made. Without such data, the primary function of sophisticated analysis systems such as the Dreyer Table (or a Pollen Aim Correction System, were any fielded) is substantially undercut if not outright lost. It is remarkable that this can be the practical reality of the most crucial battle of the war, and that discussion persists along the line that the Dreyer tables failed the British. The truth is that the Dreyer tables, which permitted every rangefinder on board to contribute data to the firing solution, offered a huge advantage over a Pollen Aim Correction System, which allowed only a single rangefinder to directly inform the calculation. Even so, the endeavour failed on want of range cut data.

The primary hardware failure of British fire control at Jutland was that the Barr & Stroud rangefinders were unable to do what they were designed to do.

See Also

• Battle of Jutland
• Dreyer Fire Control Table

Bibliography

• Admiralty, Gunnery Branch (1918). Handbook of Captain F. C. Dreyer's Fire Control Tables, 1918. C.B. 1456. Copy No. 10 at Admiralty Library, Portsmouth, United Kingdom.
• Elliott Brothers, London (1916). Captain F. C. Dreyer's Fire Control Apparatus, Mark IV. Copy 19 "as fitted in H.M.S. Royal Oak" at H.M.S. Excellent Library, Portsmouth, United Kingdom.
• Dreyer, Frederic; Usborne, Cecil through Gunnery Branch, Admiralty. (1913). Pollen Aim Corrector System, Part I. Technical History and Technical Comparison with Commander F. C. Dreyer's Fire Control System. P. 1024. in Admiralty Library, Portsmouth.
• Admiralty, Gunnery Branch. C.B. 1245. Range Tables for His Majesty's Fleet. Volume I. 1918. (9.2-inch Guns and Above.). Pub. No. OU 6089 (late CB 1245), Vol. 1 The National Archives. ADM 186/236.
• Admiralty, Gunnery Branch (1916). The Sight Manual. 1916. O.U. 6026 (late C.B. 1243). Copy No. 1749 at the The National Archives. ADM 186/216.
• Admiralty, Gunnery Branch (1930). Pamphlet on Turret Dreyer Table as Fitted in the Turrets of H.M. Battleships, and in the Transmitting Stations of Certain Cruisers. O.U. 6196 (A). Copy at Admiralty Library, Portsmouth, United Kingdom.