Osprey-class sloop

Summary

The Osprey class was a Royal Navy class of screw-driven sloops built between 1874 and 1877. Nine additional ships were built to a revised design, the Doterel-class sloop. They were the first class of ship in the Royal Navy to use glass scuttles.

Penguin
Class overview
NameOsprey-class sloop
Operators Royal Navy
CostBetween £49,217 (Cormorant) and £56,221 (Pelican)
Built1874–1877
In commission1874–1949
Completed5
Scrapped5
General characteristics [1]
TypeScrew composite sloop
Displacement1,130 long tons (1,150 t)
Length170 ft (51.8 m) (p/p)
Beam36 ft (11.0 m)
Draught15 ft 9 in (4.8 m)
Depth19 ft 6 in (5.9 m)
Installed power666–1,056 ihp (497–787 kW)
Propulsion
Sail planBarque rig
Speed9–12 knots (17–22 km/h; 10–14 mph)
Range1,480 nmi (2,740 km; 1,700 mi) at 10 knots (19 km/h; 12 mph)
Complement140
Armament

Design edit

They were of composite construction, with wooden hulls over an iron frame. Five ships of the class were built, which had been designed in 1874 by the Royal Navy's Chief Constructor, William Henry White.[1] They were the first ships in the Royal Navy to have glass scuttles instead of solid plug scuttles.[1]

Propulsion edit

The original design, as fitted to the first two ships of the class, was a single-expansion returning-rod steam engine, but the power was insufficient, and they failed to meet the contracted speed. Wild Swan and Penguin were re-engined after their first commission to match the better engines in the rest of the class.[1] In the final installation, power was provided by three cylindrical boilers, which supplied steam at 60 pounds per square inch (410 kPa) to a two-cylinder horizontal compound-expansion steam engine driving a single 13-foot-1-inch (3.99 m) screw. The power varied wildly from ship to ship, with Penguin generating only 666 indicated horsepower (497 kW) and Pelican managing nearly twice as much, at 1,056 indicated horsepower (787 kW). Because of this, top speeds ranged between 10 and 12 knots.[1][Note 1]

Armament edit

They were armed with two 7-inch (90cwt) muzzle-loading rifled guns on pivoting mounts, and four 64-pounder muzzle-loading rifled guns (two on pivoting mounts, and two broadside). Four machine guns and one light gun completed the weaponry. Wild Swan and Pelican later had the muzzle-loading guns replaced with two 6-inch (81cwt) breech-loaders and six 5-inch (31cwt) breech-loaders.[1]

Sail plan edit

All the ships of the class were provided with a barque rig,[1] that is, square-rigged foremast and mainmast, and fore-and-aft sails only on the mizzen mast.

Crew edit

They had a complement of approximately 140 men.[1]

Development edit

The design was revised in 1877 and nine ships were ordered to a modified version, the Doterel-class sloop. Identical in many respects, the Doterels lacked the graceful clipper bow of the Ospreys, although they benefited from more power.[1]

Ships edit

Name Ship Builder Laid down Launched Commissioned Fate
Wild Swan Robert Napier and Sons, Govan 14 September 1874 28 January 1876 23 August 1877 Renamed Clyde in 1904 as the Royal Naval Reserve drill ship at Aberdeen. Renamed Columbine in 1912. Sold for breaking up 4 May 1920
Penguin Robert Napier and Sons 14 July 1874 25 March 1876 23 August 1877 Sold as a crane hulk 1924, burnt out 13 December 1960
Osprey Sheerness Dockyard 1875 5 August 1876 19 April 1877 Sold for breaking 29 April 1890
Pelican Devonport Dockyard 8 March 1875 26 April 1877 29 November 1877 Sold as a supply ship 22 January 1901
Cormorant Chatham Dockyard 1875 12 September 1877 2 July 1878 Harbour hulk November 1889, renamed Rooke July 1946. Scrapped at Málaga in 1949

Notes edit

  1. ^ The lower power figures may be the trials figures from the initial installation in Wild Swan and Pelican and should be treated with caution.

References edit

  1. ^ a b c d e f g h i Winfield (2004) p.291

Bibliography edit

  • Ballard, G. A. (1939). "British Sloops of 1875: The Larger Ram-Bowed Type". Mariner's Mirror. 25 (January). Cambridge, UK: Society for Nautical Research: 35–49.
  • Preston, Antony; Major, John (2007). Send a Gunboat: The Victorian Navy and Supremacy at Sea, 1854–1904 (2nd ed.). London: Conway. ISBN 978-0-85177-923-2.
  • Roberts, John (1979). "Great Britain and Empire Forces". In Chesneau, Roger & Kolesnik, Eugene M. (eds.). Conway's All the World's Fighting Ships 1860-1905. Greenwich, UK: Conway Maritime Press. ISBN 0-8317-0302-4.
  • Winfield, R.; Lyon, D. (2004). The Sail and Steam Navy List: All the Ships of the Royal Navy 1815–1889. London: Chatham Publishing. ISBN 978-1-86176-032-6. OCLC 52620555.

External links edit