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__NOTOC__ The Coastal Class (often known as the C-Class or simply the 'Coastals') were a class of non-rigid airship or "blimp" used by the Royal Naval Air Service (RNAS) during World War I. The C-class blimp operated by the United States Navy after the war was a completely unrelated design. In total 35 Coastals were built, all at RNAS Kingsnorth, Kent. Entering service in 1916, the Coastal class remained in widespread service until 1918, with a few members of the class still in service at the signing of the Armistice, while others were replaced by the improved C-Star class as they became unfit for service. The blimps were used for long anti-submarine patrols in the Western Approaches and English Channel, protecting convoys from German U-Boats. The Coastal class was one of the first aircraft types specifically designed to detect and attack submarines.〔London, 1999〕 ==History & design== The C-Class was far from a new design. The prototype was built in 1915 by using the envelope from the No. 10 Astra-Torres airship, and a gondola built using the front-sections of two Avro seaplane fuselages joined together back-to-back to provide one tractor- and one pusher propeller. The envelope was composed of rubber-proofed fabric that was also doped to hold the gas and resist the effects of weather, and had a distinctive trilobe shape in which the two lower lobes were situated side-by-side, and the third was positioned centrally above them.〔London, 1999, p.12〕〔(Coastal Class ) The Airship Heritage Trust. Retrieved on 14 March 2009.〕 Sometimes referred to as the "ugliest" dirigibles ever made,〔 production Coastals looked very similar, but used a bespoke gondola with canvas sides built over a wooden frame. The trilobe envelope allowed the gondola to be hung closer to the envelope, reducing the overall height of the aircraft and slightly reducing head resistance. Four ballonets, two in each of the two lower lobes, were used to maintain the envelope's shape and pressure.〔〔London, 1999, p.13〕 These were kept inflated by a metal air scoop mounted in the slipstream of the forward propeller on earlier examples, and at the rear propeller on later versions. The nose of the envelope was made of aluminium sheet reinforced with bamboo canes to prevent it deforming due to the airflow pressure as the airship moved. Three tailfins were used. The two upper ones were mounted in a shallow V-tail configuration and carried the elevators, while the single vertical fin below the envelope incorporated a rudder. Ten main suspensions were incorporated in the Coastal envelope, of which seven supported the weight of the gondola, and the remaining three took the guys that allowed the 196 ft (60 m)-long airships to be handled on the ground. No landing gear was fitted, apart from two wooden skids at either end of the gondola which also protected the propellers.〔 Various engines were used on the Coastal class. The most common configuration was two water-cooled Sunbeam engines, producing 150 hp (111 kW) each. Some replaced the aft unit with a Renault engine of 220 hp (164 kW), and various airships were deployed with a 100 hp (74 kW) Berliet engine in the front position. The former change was usually an attempt to improve the Coastals' leisurely top speed, whilst the latter was an attempt to improve reliability over the Sunbeam units, which had short lives when required to run at full speed for hours at a time in the long patrols undertaken by the airships.〔London, 1999, p.13-15〕 A 1.5 horsepower (1.1 kW) ABC engine was mounted in the gondola. This drove a dynamo to power the radio and, if needed, an auxiliary ballonet blower. The standard layout was to carry two 110-gallon (500 litre) fuel tanks, one per engine. These were usually mounted within the gondola, but when using the non-standard engines, the tanks would sometimes have to be relocated to outside the gondola or even hung from the rigging. Other equipment carried in the gondola included the compressed-air tanks for the engine starters, the engine oil tanks and the sandbag ballast.〔London, 1999, p.14– applies to all information on gondola specification and armaments〕 There was no standard armament for the class. The most usual set-up consisted of at least two .303 Lewis guns. These could be mounted in a variety of places around the gondola. Another Lewis Gun was mounted on a Scarff ring on the top of the envelope to provide a token defence from attacking aircraft. This position was accessed by climbing up a light wooden- or rope ladder inside a tube running up inside the envelope. Some C-Class commanders fitted additional Lewis guns to the bottom of the gondola to provide added firepower against submarines. Firing these required the crew to lean out of the their cockpits or even stand on the landing skid to operate the weapon. The main anti-submarine armament was bombs. Most patrols carried four 100 or 112-lb (45 or 50 kg) bombs, but these could be replaced with a pair of 230-lb (104 kg) bombs or depth charges. The standard British Lee–Enfield rifle was often carried by one of the crew to destroy any mines found. A plate camera could be carried, usually used for surveys to prepare nautical charts. The standard crew was five – a pilot, a coxswain, an observer, a radio operator and a mechanic. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Coastal class airship」の詳細全文を読む スポンサード リンク
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