Supermarine Seagull и Walrus

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   Эксперименты по использованию радиального ПД Bristol Jupiter IX с толкающим винтом привели к созданию прототипа Seagull Mk V, оснащенного радиальным ПД Bristol Pegasus IIM2 мощностью 620 л. с. (462 кВт) и закрытой кабиной экипажа. Правительство Австралии заказало 24 таких самолета. После испытаний машины с металлическим корпусом на нее обратила внимание морская авиация Великобритании (Fleet Air Arm, FAA), присвоив обозначение Walrus Mk I.
   Компания "Supermarine" построила 287 самолетов, a остальные из 746 машин изготовила фирма "Saunders-Roe". В это число входит и 191 самолет Walrus Mk II с деревянным корпусом постройки "Saunders-Roe" с двигателем Pegasus VI и хвостовым колесом (вместо традиционного костыля). Самолет Walrus, способный стартовать с катапульты,начал службу в морской авиации в 1 936 году. Им оснащали линкоры и крейсера австралийских, британских и новозеландских ВМС.
   Walrus Mk II, принятый на вооружение британских ВВС в 1941 году, поступил в семь поисково-спасательных эскадрилий в метрополии и четыре эскадрильи на Ближнем Востоке, а также в одно подразделение по поиску мин. Большую часть Второй мировой войны самолет использовался практически на всех ТВД, где воевала Великобритания. Машина сыграла важную роль в поисково-спасательных службах ВМС и ВВС, сохранив жизни большому числу авиаторов. В военные годы самолет был более известен под именем "Shagbat".
   Перед началом Второй мировой войны шесть Seagull Mk V были проданы Турции, а в послевоенные годы восемь Walrus поставили Аргентине.


ТАКТИКО-ТЕХНИЧЕСКИЕ ХАРАКТЕРИСТИКИ
  
   Supermarine Walrus Mk I

   Тип: разведывательная амфибия - биплан с экипажем из четырех человек
   Силовая установка: один радиальный ПД Bristol Pegasus VI мощностью 750 л. с. (559 кВт)
   Летные характеристики: макс. скорость на высоте 1450 м - 217 км/ч; потолок 5210 м; дальность полета 966 км
   Масса: пустого 2223 кг; максимальная взлетная 3266 кг
   Размеры: размах крыла 13,97 м; длина 11,35 м; высота 4,65 м; площадь крыла 56,67 м2
   Вооружение: один 7,7-мм пулемет Vickers "K" в носовой части и один или два аналогичных пулемета в верхней стрелковой установке, под крылом до 272 кг бомб или две глубинные бомбы Mk VIII

Flight, March 1934

THE SUPERMARINE "SEAGULL" MARK V
Bristol "Pegasus" Engine

   WHEN the Society of British Aircraft Constructors held its Display at Hendon in July last year, on the Monday after the R.A.F. Display, one of the machines which attracted great attention was an entirely new type produced by the Supermarine Aviation Works. The machine made its first public appearance on that occasion, having in fact been finished but a few days previously, and the flight to Hendon being its third. In spite of this, Mr. Summers, Vickers' test pilot, handled the machine remarkably well, and caused favourable comment by, his demonstration of its capabilities. The machine was known as the "Seagull" Mark V, and was fitted with a Bristol "Pegasus" engine so mounted as to drive a "pusher" airscrew.
   Since last summer a great deal of development work has been done on the new machine, and it has now reached a stage when it can be considered quite ready, for production work to begin. In addition to such features as amphibian undercarriage and pusher airscrew drive with an air-cooled engine, the "Seagull" Mk. V is remarkable in that it has been strengthened to stand successfully the large stresses caused by launching the machine by catapult. We believe that many years ago an old flying boat was catapulted off experimentally, but that was a "dead" launch (i.e., with no one on board). Except for that, the "Seagull V" is the first amphibian flying boat to be designed specifically with catapult launching in view, and the machine may therefore be said to introduce a new phase in marine aviation. This is not the place to discuss the uses and advantages of an amphibian flying boat capable of being launched by catapult, but without going into details, it will be obvious that an aircraft which can take off from an aerodrome, the deck of a carrier, or from a catapult placed on a carrier or on a cruiser, and which can alight on land or on a carrier, as well as on the sea, has a field of action far in excess of the aircraft which is either pure landplane or pure seaplane. That a certain price has to be paid for these advantages in the form of a slightly smaller disposable load, and probably a very small reduction in performance, goes without saying. In the Supermarine "Seagull V," however, the retractable undercarriage has been so designed that, when raised, it adds but very little extra drag, the wheels being housed in the wing.
   The "Seagull V" is the very up-to-date descendant of machines in use by the R.A.F., the R.A.A.F., the Spanish and Japanese air forces ten years ago or more. The original "Seagull," it may be remembered, differed from most of the single-engined boats of those days in being a tractor. It is interesting to observe that in the latest type, although this is fitted with a radial air-cooled engine, the "pusher" arrangement has been adopted once more, thus reversing the placing as compared with the early "Seagull," but reverting to what was almost standard practice in the early days of flying boats. In a single-engined boat there are several advantages in adopting the "pusher" arrangement, notably in that the airscrew is kept well up out of the way of spray, and secondly that in picking up moorings and manoeuvring on the sea generally, the crew can use the forward deck without risk of being struck by the propeller blades as might occur in a tractor machine.
   Some weeks ago we had the privilege of witnessing catapult trials of the "Seagull V" at the Royal Aircraft Establishment, Farnborough. The large new catapult of ship's type (i.e., not the transportable type demonstrated at R.A.F. Displays) was used for the tests. The photographs at the top of this page show the stages in the launching. The machine was wheeled up the slope until the four claws of the catapult could be engaged with the fittings at the step and on the chine of the aft portion of the hull. When the four attachments had been secured, the telescopic ram of the catapult was retracted, carrying the machine with it. The Bristol "Pegasus" engine was started, and Flt. Lt. Sydney R. Ubee, of the Experimental Section, R.A.E., took his place in the machine, wedging his head firmly against the padding at the back of his head; he raised his hands in signal, the catapult crew "fired," and in the space of a few seconds the machine was in the air. In spite of the very short time in which the machine was accelerated from rest to flying speed, there was a marked absence of shock or jerk, and the impression was one of extreme smoothness. Careful watching failed to reveal any tendency of the machine to tip up or down, but whether that was due to the skill of the pilot or to the fact that two accelerating forces were at work - the catapult near the bottom of the machine and the airscrew thrust an equal distance above the centre of gravity – is difficult to say. One would expect that at the instant when the machine leaves the catapult, and the lower accelerating force is removed while the upper is increasing, there would be a tendency for the machine to dip. If such a tendency was present, it was not noticeable. Only the slow-motion film of the launch which was taken by the Vickers photographic department could reveal such details. To the eye they were imperceptible, due to the speed with which everything happened.
   The great point is that the launch proved definitely that a flying boat can be launched by catapult.

Structural Features

   In general design the Supermarine "Seagull," Mark V, is an orthodox biplane superstructure carried on an all-metal hull, with the engine mounted on struts from the top of the hull, and the top centre-section braced by four short struts from the engine mounting. The biplane wings have a single pair of struts on each side, and bracing is by streamline wires in the normal way.
   The hull of the "Seagull" is of the type which is coming more and more into use in this country: flat sides and straight-vee bottom, with a flat towards the chine where formerly reverse curves used to be found on all British flying boats. It is interesting to reflect that the flat-sided straight-vee type of hull was the earliest of all, and that curves and reverse curves were introduced later as refinements in hulls named after the late Mr. Linton Hope. Lately there has been a tendency to revert to the straight-line frames, which make construction somewhat easier and avoids the need for "panel beating," now that metal plating has been universally adopted.
   Aluminium alloys are used in the construction of the hull, and the wings are of composite construction, with built-up spars of stainless steel, and wooden ribs and secondary structure. The wing covering is fabric.
   Although this is not intended to be a technical description of the "Seagull V," a few words about the retractable undercarriage may not be out of place. Reference has already been made to the fact that this is of very neat design. Briefly, the system consists in hingeing the telescopic leg to the side of the hull. A radius rod runs from the lower end of the telescopic leg to a point a few inches above the chine. The upper end of the telescopic leg projects diagonally into the interior of the hull, where it is attached to the rod of a hydraulic plunger. When this plunger is operated by the pilot, the end of the leg is pulled down, the outer end rises, and when the limiting position has been reached, the wheel is buried in a circular recess in the wing, leaving exposed only the telescopic leg and the radius rod. In the "down" position, the telescopic leg is locked to the chine by a plunger.
   The Bristol "Pegasus" engine is, as already mentioned, mounted as a "pusher." It is carried on a monocoque nacelle, inside which is the oil tank, which at the same time acts as an oil cooler. If the machine is to be used in very hot climates, extra cooling can be obtained by fitting externally on the nacelle a Vickers-Potts oil cooler. A large manhole in the bottom of the nacelle gives access to the engine accessories, while smaller inspection holes are provided in various places to facilitate adjustments of such accessories as cannot readily be reached through the main manhole. The petrol is carried in two tanks in the upper wing, one on each side of the centre-section, and feed is by gravity to the engine. A four-bladed wooden "pusher" airscrew is fitted.

Accommodation

   The lay-out of the interior of the hull is of orthodox arrangement, but the dimensions are such that there is plenty of room everywhere. In the extreme bows is an open cockpit fitted with Scarff gun ring. A detachable cover is provided for this cockpit, in the compartment under which is stowed the mooring equipment. Then follows the pilot's compartment, with sliding windows in sides and roof. Provision is made for a second set of controls to be fitted in front of the starboard side, so that the machine can be used for instructional work if desired.
   Between the pilot's cockpit and the front spar frame is the navigator's compartment, with large table for chart box, windows for taking bearings and observations. Aft of that is the wireless operator's position, and finally behind the wings is the rear gunner's cockpit. Owing to the fact that the engine is a "pusher," the cabin is comparatively quiet; at any rate, sufficiently so to make conversation possible without telephones. This should be a valuable feature, especially if the machine is being used for training work.
   In connection with the slow-motion film mentioned on a previous page, we have, since above article was written, had an opportunity to see at Vickers House, Broadway, Westminster, not only this but also a film of the catapult launching taken at normal speed. The feature to which we referred, i.e., a slight dip at the instant the aircraft leaves the catapult, could just be seen in the normal film, and the pilot could be seen correcting it with a flick of the elevator. The slow-motion picture was taken from a different viewpoint, and did not appear to show any dip, although a slight flick of the elevator was noticed. It seems certain that the tendency to dip is by no means violent.
   The behaviour of the "Seagull V" on the water was also shown, in another film, and the slow-motion film of the take-off and alighting characteristics was extremely interesting. The machine appears to run very cleanly, and the undercarriage strut to the chine does not seem to cause any spray. As soon as any speed is attained the water seems to be flung out beyond the strut.