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Hub AI
Steam gun boat AI simulator
(@Steam gun boat_simulator)
Hub AI
Steam gun boat AI simulator
(@Steam gun boat_simulator)
Steam gun boat
Steam gun boats (SGBs) were small Royal Navy vessels built from 1940 to 1942 for Coastal Forces during World War II. The class consisted of nine steam-powered torpedo boats combining aspects of both motor torpedo boats and motor gun boats while being twice as large vessels.
They were developed in parallel with the 35-metre long Fairmile D motor torpedo boats ("dog boats"), specifically due to the need to hunt down German E-boats at a time of scarcity of suitable diesel engines. While sixty were planned, only an initial batch of nine were ordered on 8 November 1940, of which seven were completed.
The steam gun boats were conceived to answer the seeming need for a craft which was large enough to put to sea in rough weather and which could operate both as a "super-gunboat" and a torpedo carrier, combining the functions of the motor gunboat (MGB) and motor torpedo boat (MTB) in the same fashion as did the German E-boats. The Admiralty wanted Denny to produce a design that was suitable for pre-fabrication construction to enable large numbers to be built.
They were the largest of the Coastal Forces vessels, and were the only ones to be built of steel (to meet the fast production requirement – all other Coastal Forces craft were of wood). They resembled a miniature destroyer, and were perhaps the most graceful of all the craft produced during the Second World War. However their comparatively large silhouette was a drawback, making them too easy a target for the faster German craft.[citation needed]
They were 145 ft 8 in (44.40 m) long and had a displacement of 172 tons (202 tons fully fuelled). They were powered by two 4,000 shp (2,983 kW) Metropolitan-Vickers geared steam turbines using special LaMont boilers. These boilers proved to be particularly vulnerable to attack and – once the vessel had broken down – required a major effort to repair. Steam had the advantage of quietness but demanded a large hull. Large wooden hulls were not feasible for mass production, so steel was used. This meant hulls and machinery were beyond the scope of the small yards engaged in the rapid expansion of the coastal forces, and the SGB thus competed for berths in yards already hard put to produce urgently required convoy escorts. Also they competed in the demand for mild steel and steam power plants against the more urgently demanded destroyers; accordingly the planned 51 further vessels were not ordered, and the two units ordered from Thornycroft were not completed after air-raid damage. The seven vessels constructed were built by Yarrow, Hawthorn Leslie, J. Samuel White and William Denny and Brothers, entering service by the middle of 1942.[citation needed]
Fuel consumption was heavy. A disadvantage was that, while a petrol boat could start from cold and get away immediately, the SGB had to remain in steam. Over time the addition of 18 mm (0.7 in) protective plate over the sides of the boiler and engine rooms, together with the extra armament and crew, increased the displacement to 260 tons and their service speed was consequentially reduced to 30 knots.[citation needed]
Veritable battleships of the coastal forces, the steam gun boats were heavily armed and could maintain high speed in a seaway. In action E-boat commanders respected the SGBs almost as much as destroyers as a single well-placed shot from their three-inch guns could disable or sink an E-boat.[citation needed]
Their armament was arranged with the three-inch gun on the aft deck behind the superstructure, just aft of the torpedo tubes that angled out on either side of the superstructure. There were a pair of (57 mm) six-pounder guns fore and aft, and two twin Oerlikon 20 mm cannons, one in the apex of the bow and one on the stern superfiring over the three-inch gun. Machine guns were mounted in twin mounts on either side of the bridge.
Steam gun boat
Steam gun boats (SGBs) were small Royal Navy vessels built from 1940 to 1942 for Coastal Forces during World War II. The class consisted of nine steam-powered torpedo boats combining aspects of both motor torpedo boats and motor gun boats while being twice as large vessels.
They were developed in parallel with the 35-metre long Fairmile D motor torpedo boats ("dog boats"), specifically due to the need to hunt down German E-boats at a time of scarcity of suitable diesel engines. While sixty were planned, only an initial batch of nine were ordered on 8 November 1940, of which seven were completed.
The steam gun boats were conceived to answer the seeming need for a craft which was large enough to put to sea in rough weather and which could operate both as a "super-gunboat" and a torpedo carrier, combining the functions of the motor gunboat (MGB) and motor torpedo boat (MTB) in the same fashion as did the German E-boats. The Admiralty wanted Denny to produce a design that was suitable for pre-fabrication construction to enable large numbers to be built.
They were the largest of the Coastal Forces vessels, and were the only ones to be built of steel (to meet the fast production requirement – all other Coastal Forces craft were of wood). They resembled a miniature destroyer, and were perhaps the most graceful of all the craft produced during the Second World War. However their comparatively large silhouette was a drawback, making them too easy a target for the faster German craft.[citation needed]
They were 145 ft 8 in (44.40 m) long and had a displacement of 172 tons (202 tons fully fuelled). They were powered by two 4,000 shp (2,983 kW) Metropolitan-Vickers geared steam turbines using special LaMont boilers. These boilers proved to be particularly vulnerable to attack and – once the vessel had broken down – required a major effort to repair. Steam had the advantage of quietness but demanded a large hull. Large wooden hulls were not feasible for mass production, so steel was used. This meant hulls and machinery were beyond the scope of the small yards engaged in the rapid expansion of the coastal forces, and the SGB thus competed for berths in yards already hard put to produce urgently required convoy escorts. Also they competed in the demand for mild steel and steam power plants against the more urgently demanded destroyers; accordingly the planned 51 further vessels were not ordered, and the two units ordered from Thornycroft were not completed after air-raid damage. The seven vessels constructed were built by Yarrow, Hawthorn Leslie, J. Samuel White and William Denny and Brothers, entering service by the middle of 1942.[citation needed]
Fuel consumption was heavy. A disadvantage was that, while a petrol boat could start from cold and get away immediately, the SGB had to remain in steam. Over time the addition of 18 mm (0.7 in) protective plate over the sides of the boiler and engine rooms, together with the extra armament and crew, increased the displacement to 260 tons and their service speed was consequentially reduced to 30 knots.[citation needed]
Veritable battleships of the coastal forces, the steam gun boats were heavily armed and could maintain high speed in a seaway. In action E-boat commanders respected the SGBs almost as much as destroyers as a single well-placed shot from their three-inch guns could disable or sink an E-boat.[citation needed]
Their armament was arranged with the three-inch gun on the aft deck behind the superstructure, just aft of the torpedo tubes that angled out on either side of the superstructure. There were a pair of (57 mm) six-pounder guns fore and aft, and two twin Oerlikon 20 mm cannons, one in the apex of the bow and one on the stern superfiring over the three-inch gun. Machine guns were mounted in twin mounts on either side of the bridge.