Difference between revisions of "Hawkins Class Cruiser (1917)"

Latest revision as of 10:30, 27 March 2020

Four of the five cruisers of the Hawkins Class (sometimes called the Raleigh Class or Effingham Class and (maddeningly!) Cavendish Class) that were ordered were completed as cruisers, but one was completed as the aircraft carrier Vindictive. Although their 7.5-in guns lent them to the notion of being heavy cruisers, their single pedestal mountings still resembled the British model of an early light cruiser.

Machinery

Electrical Distribution Scheme^[1]

Boilers

Engines

Generators

In 1916, it was approved that the ships were to be given four 105-kw dynamos at 220 volts.^[2]

Armament

7.5-in Guns

The guns had armoured shields of 1 inch thickness on the face, sides and top, weighing 7.25 tons.^[3]

The mountings were C.P. V.^[4]

Torpedoes

• Two 21-in submerged broadside tubes forward, angled 90 degrees and horizontal.^[5]
• Four 21-in above-water tubes, fixed and with gyro angle pads for adjusting torpedoes.^[6]

Though it was envisioned that they would eventually use the 21-in Mark V torpedo, in mid-1920 it was ordered that they should use the 21-in Mark IV* torpedo as a temporary measure.^[7]

Fire Control

Range Dials

As of 1920, the four ships completed as cruisers had a Range Dial Type H and a Range Dial Type J.^[8]

Rangefinders

By 1921, the ships were equipped as follows:^[9]

• Spotting top: 12ft F.Q. 2 on M.Q. 1 mounting
• After control platform: 15ft F.T. 24 on M.Q. 11, 9ft F.Q. 2 on M.P. 2
• High Angle: 2m F.T. 29 on M.T. 6 or M.T. 10

Mechanical Aid-to-Spotter

By 1919, all the ships were likely equipped with four Mechanical Aid-to-Spotter Mark II*s, with Elliott's Bearing Transmission. The installations generally consisted of placing one on each side of the foretop, driven by flexible shafting from a gearbox on the director tower.^[10]

Supplies of these devices begane in June 1918.^[11]

In 1917, it was decided that these should have mechanical links from the director and pointers indicating the aloft Evershed's bearing.^[12]

Evershed Bearing Indicators

The ships almost surely had Evershed gear for gun control from delivery, as approval for their outfits was issued in 1916.^[13]

Directors

They were completed with directors in place.

The Elevation Receivers for the 7.5-in battery were 4-in Triple Type with mechanical tilt correctors, Pattern H. 12. They could indicate elevations up to 30 degrees. The Small Type Training Receivers were pattern number 20 on #1 and #2 and P3 and S3, whereas #4, #5 and #6 had pattern number 21.^[14]

Dreyer Table

In 1918, it was planned that all five projected vessels receive Dreyer Table Mark I*s,^[15] but it is unclear as to whether any of the ships received these or the more advanced types they are later recorded as possessing. By 1930, Hawkins had a Dreyer Table Mark IV* of unrecorded register number.^[16] At that time, Frobisher and Effingham were noted as having Mark III* tables.^[17] As Raleigh was wrecked in 1922, little is known of her equipment.

Fire Control Instruments

Torpedo Control

Torpedo Control, as proposed in 1916^[18]
Note that it was later determined that the transmitters shown in the T.S. and the corresponding receivers in the control positions was not to be provided, as the information would not be available in the T.S..^[19]

Torpedo Control Circuits^[20]

The torpedoes could be controlled and fired from the C.T. or the T.C.T., with firing keys routed through C.O.S.es in the T.S..

The CT had

• Two gyro angle transmitters
• Two order transmitters
• One range receiver (from T.C.T.)
• One range and torpedo deflection transmitter (to T.C.T.)
• One bearing transmitter (to T.C.T.)

The T.C.T. had

• Two gyro angle transmitters
• Two order transmitters
• One range transmitter (to C.T.)
• One range and torpedo deflection receiver (from C.T.)
• One bearing transmitter (from C.T.)

The tubes had:

• Two gyro angle receivers, one from C.T. and one from T.C.T.
• Two order receivers, one from C.T. and one from T.C.T.

All three locations had fixed Navyphone connections to the other two, and the C.T. also had voice pipes to the torpedo tubes.

In 1919, it was decided that Hawkins should receive a Renouf Torpedo Tactical Instrument Type B, and that one should be allocated for the other three units as they were completing construction.^[21] A year later, the allocation plan was re-iterated.^[22]

See Also

Footnotes

Bibliography