If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
SPAD S.XIII
https://en.wikipedia.org/wiki/SPAD_S.XIII
The SPAD S.XIII was a French biplane fighter aircraft of the First World War, developed by Société Pour L'Aviation et ses Dérivés (SPAD) from the earlier and highly successful SPAD S.VII. During early 1917, the French designer Louis Béchereau, spurred by the approaching obsolescence of the S.VII, decided to develop two new fighter aircraft, the S.XII and the S.XIII, both utilizing a powerful new geared version of the successful Hispano-Suiza 8A engine. The cannon armament of the S.XII was unpopular with most pilots, but the S.XIII proved to be one of the most capable fighters of the war, as well as one of the most-produced, with 8,472 built and orders for around 10,000 more cancelled at the Armistice. By the end of the First World War, the S.XIII had equipped virtually every fighter squadron of the Aéronautique Militaire. In addition, the United States Army Air Service also procured the type in bulk during the conflict, and some replaced or supplemented S.VIIs in the Royal Flying Corps (RFC), pending the arrival of Sopwith Dolphins. It proved popular with its pilots; numerous aces from various nations flew the S.XIII during their flying careers. Following the signing of the Armistice of 11 November 1918, which effectively marked the end of the First World War, surplus S.XIIIs were sold in great numbers to both civil and military operators throughout the world. The origins of the SPAD S.XIII lies in the performance of its predecessor, the SPAD S.VII, a single-seat fighter aircraft powered by a 150-horsepower (110 kW) direct drive Hispano-Suiza 8A water-cooled V-8 engine and armed with a single synchronised Vickers machine gun. The type demonstrated excellent performance for the time, entering operational service with the French Aéronautique Militaire during August 1916. By early 1917, however, the S.VII had been surpassed by the latest German fighters such as the Albatros D.I. The emergence of increasingly capable German fighters, which soon resulted in a shift in aerial supremacy towards the Central Powers, led to calls for superior aircraft to be developed and procured. French flying ace Georges Guynemer personally lobbied for an improved version of the S.VII, telling the SPAD designer Louis Béchereau that "The 150 hp SPAD is not a match for the Halberstadt ... More speed is needed." An initial and quick solution to the problem was to increase the compression ratio of the Hispano-Suiza engine, which increased its power to 180 hp (130 kW) to provide for significantly improved performance, allowing the SPAD S.VII to remain competitive for the time being. Spanish manufacturer Hispano-Suiza were already in the process of developing a more powerful geared version of the 8A engine, and this engine was unsurprisingly chosen by Béchereau to power two developed versions of the S.VII. The British S.E.5a and Sopwith Dolphin fighters would also be powered by the same engine. Design The SPAD S.XIII was a single-engine biplane fighter aircraft. In terms of its construction, it shared a similar configuration and layout to the earlier S.VII, featuring a mainly wooden structure complete with a fabric covering; however, it was generally larger and heavier than its predecessor. Other changes included the tapered chord of its ailerons, the rounded tips of the tailplanes, bulkier cowling accommodating the gear-drive Hispano-Suiza 8B engine choice, and enlarged fin and rudder. The S.XIII was armed with a pair of forward-mounted Vickers machine guns with 400 rounds per gun, which took the place of the single gun that had been used on the earlier aircraft. The S.XIII featured relatively conventional construction, that being a wire-braced biplane with a box-shaped fuselage and a front-mounted engine, except for its interposed wing struts located half-way along the wing span, which gave the fighter the deceptive appearance of being a double-bay aircraft instead of a single bay. This change prevented the landing brace wires from whipping and chafing during flight, and was attributed by Andrews as a key factor for the aircraft's high rate of climb. Otherwise, it had an orthodox structure, comprising wooden members attached to metal joint fixtures. The fuselage consisted of four square-section longerons, complete with wooden struts and cross-members while braced with heavy-gauge piano wire; wire cable was instead used for the flying and landing wires. To facilitate its two-hour endurance, the S.XIII was furnished with an assortment of underbelly fuel tanks were held within the forward fuselage area; these were fed into the main service tank located in the center of the upper wing by an engine-driven pump. Similar pumps were used for supplying pressurised oil and water circulation between the engine's radiator and a header tank in housed within the upper wing. The circular nose radiator incorporated vertical Venetian-style blinds as a means of regulating the temperature of the engine. The upper wing was a single-piece structure, featuring hollow box-section short spars which connected with linen-bandaged scarf joints, Andrews claims that long runs of spruce were difficult to obtain. The ribs consisted of plywood webs and spruce capping strips, which were internally braced with piano wire. The upper wing was provisioned with ailerons, which were actuated by the pilot via a series of tubular pushrods which ran vertical directly beneath the ailerons, with external, 90º bellcranks exposed above the lower wing panels' top fabric covering. The lower wing consisted of spruce leading edges and wire-cable trailing edges, while the surfaces were fabric-covered and treated with aircraft dope to produce a scalloped effect, much as with the contemporary German Fokker D.VII that also used a wire trailing-edge component, along the trailing edges. While the forward Vickers machine guns were installed as standard, they were not always present upon all aircraft. As a result of fears of a shortage of Vickers guns during the last few months of the war, several American squadrons equipped with the S.XIII decided to replace their existing Vickers .303 machine guns with the lighter-weight (25 lbs/11.34 kg apiece) .30/06-calibre Marlin Rockwell M1917 and M1918 aircraft machine guns, saving some sixteen pounds (7.3 kg) in weight over the twin-mount Vickers' total weight of 66 lbs (29.94 kg) for the guns alone. Reportedly, by the end of the war, roughly one half of the aircraft in American service had been converted in this fashion. Role biplane fighter National origin France Manufacturer SPAD Designer Louis Béchéreau First flight 4 April 1917 Primary users Aéronautique Militaire Royal Flying Corps (Royal Air Force from April 1918) United States Army Air Service Number built 8,472 During May 1917, only one month following the type's maiden flight, deliveries to the Armée de l'Air commenced. The new aircraft quickly became an important element in the French plans for its fighter force, being expected to replace the SPAD S.VII as well as the few remaining Nieuport fighters in front line service. However, these plans were disrupted by deliveries occurring at a much slower rate than had been initially forecast; by the end of March 1918, 764 fighters had been delivered compared with a planned force of 2,230. Eventually, the S.XIII equipped virtually every French fighter squadron, comprising 74 Escadrilles, during the First World War. At the end of the war, plans were underway to replace the S.XIII with several fighter types powered by the 300 hp (220 kW) Hispano-Suiza 8F, such as the Nieuport-Delage NiD 29, the SPAD S.XX and the Sopwith Dolphin II. These plans lapsed following the signing of the Armistice of 11 November 1918, which ended the First World War and the SPAD S.XIII remained in French service as a fighter aircraft until 1923. The S.XIII was flown by numerous famous French fighter pilots such as Georges Guynemer, Rene Fonck (the highest scoring Allied ace, credited with 75 victories) and Charles Nungesser (45 victories), and also by the leading Italian ace Francesco Baracca (34 victories). Aces of the United States Army Air Service who flew the S.XIII include Eddie Rickenbacker (America's leading First World War ace with 26 confirmed victories) and Frank Luke (18 victories). Andrews attributes the S.XIII's natural stability, which lent itself to being a steady gun platform, as having been a key attribute for its success. USAAS Other Allied forces were quick to adopt the new fighter as well; the SPAD XIII equipped 15 of the 16 operational American pursuit squadrons of the USAAS by the signing of the Armistice. Even prior to America's entry into the conflict, American volunteers flying with the Allies had been piloting the type. Nearly half of the 893 purchased by the United States were still in service by 1920. In the United States, some S.XIIIs were re-engined with 180 hp Wright-Hispano engines to improve reliability and to prepare pilots for the new Thomas-Morse MB-3 fighter (which used SPAD-type wings in its construction) in 1922; according to Andrews, the Wright-Hispano engine was incapable of matching the performance of the original powerplant. Specifications (SPAD S.XIII) General characteristics Crew: 1 Length: 6.25 m (20 ft 6 in) Wingspan: 8.25 m (27 ft 1 in) late examples had a span of 8.08 m (26.5 ft) Height: 2.60 m (8 ft 6 in) Wing area: 21.11 m2 (227.2 sq ft) late examples had a wing area of 20.2 m2 (217 sq ft) Empty weight: 601.5 kg (1,326 lb) Gross weight: 856.5 kg (1,888 lb) Powerplant: 1 × Hispano-Suiza 8Ba, Bb or Bd Water cooled 8-cylinder vee-type, 150 kW (200 hp) Performance Maximum speed: 211 km/h (131 mph, 114 kn) at 1,000 m (3,300 ft) 208.5 km/h (129.6 mph; 112.6 kn) at 2,000 m (6,600 ft) 205.5 km/h (127.7 mph; 111.0 kn) at 3,000 m (9,800 ft) 201 km/h (125 mph; 109 kn) at 4,000 m (13,000 ft) 190 km/h (120 mph; 100 kn) at 5,000 m (16,000 ft) Endurance: 2 hours Service ceiling: 6,800 m (22,300 ft) Time to altitude: 2 minutes 20 seconds to 1,000 m (3,300 ft) 5 minutes 17 seconds to 2,000 m (6,600 ft) 8 minutes 45 seconds to 3,000 m (9,800 ft) 13 minutes 5 seconds to 4,000 m (13,000 ft) 20 minutes 10 seconds to 5,000 m (16,000 ft) Armament Guns: 2 x .303 in (7.70 mm) Vickers machine guns or on USAS Examples, 2 x Marlin M1917 or M1918 machine guns Bombs: 4 x 25 lb (11 kg) Cooper bombs * |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
SPAD S.VII pics [8/8] - SPAD S XIII not VII ru.jpg (1/1) | Miloch | Aviation Photos | 0 | February 25th 19 03:48 PM |
SPAD S.VIII [12/21] - SPAD XIII Cockpit.jpg (1/1) | Miloch | Aviation Photos | 0 | June 25th 16 12:50 AM |
Spad XIII 1927 | Dominique Lecarpentier | Aviation Photos | 0 | June 16th 12 01:06 PM |
MAE : SPAD VII and XIII | jmp | Aviation Photos | 0 | February 25th 08 08:57 PM |
MAE : SPAD XIII | jmp | Aviation Photos | 0 | February 25th 08 08:51 PM |