Renown Class Battlecruiser (1916)

Overview of 2 vessels
Citations for this data available on individual ship pages
Name	Builder	Laid Down	Launched	Completed	Fate
Renown	Fairfield Shipbuilding and Engineering Company, Govan	25 Jan, 1915	4 Mar, 1916	Sep, 1916	Sold 19 Mar, 1948
Repulse	John Brown & Company, Clydebank (Ship no. 443)	25 Jan, 1915	8 Jan, 1916	Aug, 1916	Sunk 10 Dec, 1941

Machinery

Generators

One 175 kw oil generator and three 200 kw steam generators, with an additional 200 kw steam generator added in 1916 or later.

Radio

According to the ambitions of 1909, these ships had Service Gear Mark II wireless upon completion.

Armament

Main Battery

• six 15-in Mark I B.L. guns in three twin turrets

Secondary battery

• five triple 4-in Mark IX guns
• two 4-in Mark IX guns on P. XII mountings

Torpedoes

• two submerged 21-in tubes on the broadside

Guns

The 4-inch guns had blue-tinted loading lights with adjustable shades that would illuminate the breech for night action. These sorts of lights are visible on other guns in many photos. The triple gun mounts had a single switch to control its three lights, located near the assistant trainer's seat.

Torpedoes

• Two Service Bar 21-in submerged broadside tubes forward depressed 2 degrees and bearing 90.
• Eight above water tubes, four each side in pairs fixed at 90 degrees and with gyro angle pads for adjusting torpedoes were initially envisioned, but apparently not fitted as built.

The submerged tubes could not be fired at speeds over 31 knots, as the bar would bend.

In 1917, these tubes were firing 21-in Mark II***** torpedoes.

Fire Control

Range Dials

As of 1920, Renown had two Range Dial Type Cs and Repulse had two Type Ds.

Rangefinders

By 1921, the ships were equipped as follows:

• "A" turret (Renown): 15ft F.T. 24 on M.G. 8 mounting
• "A" turret (Repulse): 30ft F.X. 2 on M.G. 18 mounting
• "B" turret: 15ft F.T. 24 on M.G. 8
• "Y" turret: 30ft F.X. 2 on M.G. 14
• Fore top: 12ft F.Q. 2 on M.P. 3
• Armoured tower: 15ft F.T. 24 on M.W. 1, 30ft F.X. 2 on M.G. 16
• T.C.T.: 15ft F.T. 24 on M.G. 10
• Fore bridge: two 9ft F.T. 24s on M.G. 13 mountings
• H.A. platform: 2m F.T. 29 on M.T. 6

By March 1920, Renown had the following rangefinder outfit:

• Two 30-ft in "Y" turret and in back of G.C.T.
• Four 15-ft in "A" and "B" turrets, T.C.T. and G.C.T.
• One 12-ft in spotting top
• Two 9-ft on fore bridge (for torpedo control)
• One 2m F.T. 29 H.A. R.F. on control top (fitted 1917)

At the same time, Repulse was similar, but had snuck in one more 30-ft R.F.:

• Three 30-ft in "A" and "Y" turrets and in back of G.C.T.
• Three 15-ft in "B" turret, T.C.T. and G.C.T.
• One 12-ft in spotting top
• Two 9-ft on fore bridge (for torpedo control)
• One 2m F.T. 29 H.A. R.F. on control top (fitted 1917)

Phones

Secondary Battery

Navyphones for 4-in Battery

Fire Control and Bells for 4-in Battery

Each 4-in triple mounting had a Pattern 3333 Navyphone for its officer, and a set of Pattern 3225 Telaupad receivers for each of its three sightsetters. The single 4-in guns were similar, but with a single telaupad receiver for the sightsetter. The 4-in T.S. had a pair of Pattern 3334 Navyphones plugged into its exchange board.

Other remote stations from the T.S.'s exchange board were:

• One Pattern 3331 Navyphone in 15-in G.C.T.
• Two 3334s (apparently teed off from each other in a junction box) in each of
  • Forward night defence position
  • Aft night defence position
  • Spotting top
• One 3331 with telaupad pair in each of
  • Forward 4-in director tower (fed from line feeding the spotting top's 3334s)
  • Aft 4-in director tower

Evershed Bearing Indicators

The ships contained comprehensive systems for main and secondary battery control.

In 1917, it was approved that capital ships of Dreadnought class and later should have Evershed equipment added to their C.T., able to communicate with either the fore top or the G.C.T.. If there were not enough room in the C.T., a bearing plate with open sights and 6-power binoculars would be added to the C.T.. At the same time, all directors were to be fitted with receivers and, "as far as possible", ships were to have fore top, G.C.T. and controlling turrets fitted to transmit as well as receive, though this was noted as being impossible in some earlier ships.

Main Battery

15-in Evershed System

There were four transmitting positions and eight receiving positions. Local C.O.S.es at the transmitting positions to select between port and starboard and a selector switch in the 15-in T.S. controlled the signal routing.

Transmitting positions:

1. Spotting top (p&s, with local C.O.S.)
2. C.T. (p&s, with local C.O.S.)
3. G.C.T. (p&s, with local C.O.S.)
4. "X" turret

Positions 1 & 2 were alternatives to each other and could not be used at same time (a C.O.S. in the 4-in T.S. determined which was in use). Likewise, positions 3 and 4 were mutually exclusive as determined by a second C.O.S.. Each position had a junction box of some kind, which may have had a selector switch to choose port or starboard transmitters.^[Inference]

Eight receiving positions:

• Turrets "A", "B" and "Y": open faced indicator (for Turret Director Trainer?) and a special indicator (for trainer?)
• Spotting top (indicators suitable for binoculars)
• Light aloft director tower
• Armoured director tower
• Conning tower (indicators suitable for binoculars)
• Gun control tower (indicator suitable for dumaresq)

Secondary Battery

4-in Evershed System

There were eight transmitting positions and nine receiving positions. Changeover switches and a selector switch in the 4-in TS controlled the signal routing.

Transmitting positions, in 4 port and starboard pairs:

1. Night defence position forward (p&s)
2. Spotting top (p&s)
3. Night defence position aft (p&s)
4. Manoeuvring platform (p&s)

Positions 1 & 2 were alternatives to each other and could not be used at same time (a COS in the 4-in TS determined which was in use). Likewise, positions 3 and 4 were mutually exclusive as determined by a second COS. Note the difference from the main battery system, where (say) the spotting top's port and starboard transmitters can be used at the same time here whereas only the main battery's transmitter in the spotting top selected at the local COS can be used.

Nine receiving positions with open-faced indicators near the trainers:

1. Forward 4-in director
2. Aft 4-in director
3. Single 4-in gun (port)
4. Single 4-in gun (starboard)
5. Five separate groups of 4-in guns

Mechanical Aid-to-Spotter

At some point, both were likely equipped with four Mechanical Aid-to-Spotter Mark IIs:

• one on each side of the foretop, driven by flexible shafting from the Evershed rack on the director
• one on each side of the Gun Control Tower employing an electrical F.T.P. system.

As the need for such gear was apparently first identified in early 1916, it seems likely that these installations were effected well after Jutland.

In 1917, it was decided that these should have mechanical links from the director and pointers indicating the aloft Evershed's bearing.

Directors

Both ships were completed with directors for main batteries installed, but the secondary batteries were delayed until each ship was in service for a month (see ship pages for details).

Main Battery

15-in Elevation & Training Circuits

15-in Firing Circuits

These ships were fitted with 2 cam-type tripod-mounted directors, one in an armoured tower and one in a light aloft tower. There were no directing guns.

The guns could be divided into a forward ("A" & "B") and aft ("Y") groups. Inferring from other ships with 2 directors, a C.O.S. in the T.S. permitted these control options:

• All guns on aloft director
• All guns on armoured director
• Forward group on aloft director, aft group on armoured director

It is likely that each gun had a local C.O.S. with 3 positions:^[Inference]

• Gunlayer's Firing (aux and main circuits connected to local triggers)
• Director 1 (local main to director main, local aux to director aux)
• Director 2 (local main to director aux, local aux to director main)

The turret Elevation Receivers were Pattern H. 5, capable of 20 degrees elevation.

Secondary Battery

4-in Elevation & Training Circuits

The 4-in guns were supported by a pair of pedestal-mounted directors with double cam grooves and two rollers, one forward (on foremast below the spotting top) and one aft (on mainmast). This placement helped support that subset of the guns capable of firing to either side.

The guns converged in training on the forward director; when the aft director was in use, it would itself be converged to the forward director to make it work right.

Each mounting had a five position C.O.S. offering these options:

• DIrector 1; the main director pistol fires the guns on the main circuit, and auxiliary pistol fires those on the auxiliary circuit
• Director 2; crosses the pistol/circuit relationships in Director 1, above
• Simultaneous 3; the gunlayer at "either" (any?) gun on the mounting has main pistol to main circuit and aux pistol to aux circuit
• Simultaneous 4; crosses the pistol/circuit relationships in Simultaneous 3, above
• Individual; each gunlayer's pistols fire his own gun only

The Elevation Receivers on the two single 4-in guns were 6-in P. VIII Type with hand tilt correctors, Pattern F.C. 3, capable of 25 degrees elevation. Those on the triple mounts were 4-in Triple Type, capable of 30 degree elevation and Pattern H. 11. The Small Type Training Receivers were pattern number 20 on P1, P2, S1 and S2, whereas #3, #4 and #5 had pattern number 21.

Navyphones

Torpedo Control Navyphones

The navyphone support for the submerged torpedo flats were similar to those in Hood.

Transmitting Stations

These ships had a T.S. for their 15-in guns and another for their 4-in guns.

Dreyer Table

The ships each had a Mark IV* Dreyer Table, probably from completion, and an unknown number of Dreyer Turret Control Tables installed at an unknown time.

Fire Control Instruments

Main Battery Fire Control
The variety of Marks employed prompts suspicion of the simple descriptions offered of other ships' equipment.

The Annual Report of the Torpedo School, 1915 shows that these ships had quite a loose sense of adherence to Mark numbers in their bill of materials, but included the following:

• Vickers F.T.P. Mark IV range transmitters
• Vickers F.T.P. Mark IV* deflection transmitters
• Vickers F.T.P. Mark III range and deflection receivers (also for repeats)
• Mark III* Barr and Stroud single order transmitter, Mark III receiver
• Mark III Barr and Stroud single range instruments
• Mark I Barr and Stroud fall-of-shot instruments
• Mark III Barr and Stroud combined range, order, deflection instruments
• Mark III* Barr and Stroud rate instruments (some transmitters Mark IV)
• Mark IV Barr and Stroud bearing instruments
• Captain's Bell Pattern 139 and push Pattern 1388
• Buzzer Pattern 1380
• Key Pattern 872

Torpedo Control

By 1917-1918, a number of common Torpedo Control equipment packages were to be provided to those ships not already sporting them.  Those for the 21-in torpedo ships follow.

Torpedo Control Data between C.T. and T.C.T..

The data instruments to be wired between C.T. and T.C.T. to share range, order and deflection data provided a single deflection transmitter in the T.C.T. so that the results of the torpedo plot to be sent to the single deflection receiver in the C.T. for the information of the Torpedo Control Officer.  Conversely, a combined range and deflection transmitter forward allowed the T.C.O. to send back the deflection and intended firing range to the secondary T.C.O. in the T.C.T..

Torpedo Control Evershed

The 21-in torpedo ships were also to be provided with Evershed transmitters in the C.T. and a receiver at the torpedo rangefinder in the T.C.T. in order to ensure that it was obtaining data on the intended target.  Limited "slit space" in the C.T. required that the customary binocular-based transmitters be foregone in favour of placing the transmitter on or below the floorboards and to drive it by a shaft from a Torpedo Deflection Sight Mark IV.  A control key on the transmitter allowed it to indicate when it was controlling the remote rangefinder or not.

Finally under the 1917-1918 mandate, sufficient instruments were to be provided to permit the Fore Bridge to communicate with the tubes.

In mid-1920, it was envisaged that each ship should receive a single Torpedo Control Disc Mark III* and a pair of mounting brackets to be installed in their primary torpedo control position.

Rangefinders

The rangefinder in the T.C.T. was a 9-foot F.T. 24 on an M.Q. 10 mounting. Sometime, likely not before 1918, these were to be upgraded to 15-foot instruments, probably also F.T. 24, with new armoured hoods and racers and training driving the hood directly rather than through the rangefinder mounting.  These rangefinders lacked hand-following gear to facilitate in transmission of range cuts, and when it was considered as an addition around 1917, space concerns were causing issues.  As part of the same initiative, a pair of 9-foot instruments was to be added on each side of the bridge.

Alterations

In 1916, it was approved that another 200 kw steam dynamo be added to the Revenge, Queen Elizabeth, Renown and (possibly) Furious classes, as the loss of any of the other four sets could impose an undue burden on the remaining generators, especially in a night action. Prior to the addition, the Renown class ships generated 775 kw, or 3,400 amperes.

In mid-1920, it was decided that the ships should each each receive a Renouf Torpedo Tactical Instrument Type B.

See Also

• Wikipedia

Bibliography

• H.M.S. Vernon. (Jan 1916) Annual Report of the Torpedo School, 1915. C.B. 1166. Copy 1025 at The National Archives. ADM 189/35.
• Admiralty, Technical History Section (1919). The Technical History and Index: Fire Control in H.M. Ships. Vol. 3, Part 23. C.B. 1515 (23) now O.U. 6171/14. At The National Archives. ADM 275/19.
• Admiralty, Gunnery Branch (1914). Handbook for Fire Control Instruments, 1914. G. 01627/14. C.B. 1030. Copy 1235 at The National Archives. ADM 186/191.
• Admiralty, Gunnery Branch (1917). The Director Firing Handbook. O.U. 6125 (late C.B. 1259). Copy No. 322 at The National Archives. ADM 186/227.
• 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.