Gloster Gladiator Mk I and II

Even so, the Gamecock had its flaws. For instance, the aeroplane tended to mush downwards when recovering from a high-speed dive or when pulling high-g in a turn. Like the Grebe, it also suffered from a propensity to wing (and tail) flutter and often exhibited pernicious spin characteristics. The former was attributed to the patented Gloucestershire High Lift Biplane (HLB) wings the type had inherited from the Grebe, while its short-coupled fuselage was identified as the primary cause of its spinning problems. Although the wing flutter problem was eventually cured in 1927 by the simple expedient of fitting V-shaped bracing struts to the HLB upper-wing overhang (in the process robbing the Gamecock of a few miles per hour off its top speed, and causing the fighter to receive the unflattering soubriquet, "Folland's Cock's Cradle"), the spinning problem was never fully resolved, and these defects led Folland to adopt a more cautious engineering approach in his key future designs.
It is therefore perhaps no coincidence that, by the second half of the 1920s, the company – now renamed Gloster (see endnotes) - had become wedded to the idea of the use of metal in aircraft structures. Folland had for years been championing the use of such material despite the reluctance of some of the company's directors (who had been around since the earliest days of the company's existence and were steeped in the woodworking tradition) to make the switch. Finally, in 1926/27, following the personal purchase of a fifty per cent interest in the Steel Wing Company7 by Gloster's far-seeing founder, Hugh Burroughes, he had succeeded in producing a metal version of the Gamecock to meet an Air Ministry specification issued in 1925 (F.16/25). Known as the Goldfinch, it was built mainly of steel, aluminium, and duralumin, alloys which demonstrably eliminated the wing and tail flutter to which the Gamecock and Grebe had been prone. Although in a revised form it was ultimately knocked out of the competition to be the RAF's new all-metal day and night fighter (as envisaged by specification F.9/26), its design and construction afforded Folland invaluable experience with metal airframes and left him well prepared to start on the design of an aircraft to meet an Air Ministry specification issued in the summer of 1927 (F.20/27).
However, it was now apparent that the move to all-metal construction made Gloster's Sunningend factory an unsuitable base for future production, so it purchased the nearby airfield of Hucclecote (sometimes referred to as Brockworth), seven miles to the south-west, together with its adjacent hangars and neighbouring office space. Gloster staff were already very familiar with the airfield as, lacking its own, the company had hitherto sent its new designs there by road for flight testing. Now, with Hucclecote as Gloster's permanent operational base, the SS.18 began to take shape.

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Like the unrealistic Air Ministry specification F.9/26 before it (for which the Goldfinch, and all the other submissions, had contended unsuccessfully), the essential requirements of the more viable F.20/27 were for an all-metal day and night fighter powered by a radial engine and armed with just two guns. In official circles, it was now widely accepted that metal structures would be mandatory in the next generation of fighter aircraft to prevent the kind of wing and tail flutter problems that had troubled the Gamecock, particularly as higher performance was demanded, and airframe stresses increased accordingly. Indeed, the need for significantly greater speed and climb from RAF fighters had become embarrassingly obvious to Air Ministry strategists when, from 1926, the new Fairey Fox light bomber, with a top speed of more than 220mph, routinely outran and outclimbed the current crop during the annual Air Defence Exercises. Remarkably, pilots of the Fox were eventually instructed to fly no faster than 140mph to give the defending fighters a reasonable chance of intercepting them!
Against this background, Folland conceived the SS.18, the first direct forerunner of his next major project, the Gladiator. Although confident that it would meet the requirements of F.20/27, in the event it would be the Bristol Bulldog that the RAF procured as its new fighter. Nonetheless, assured in the belief that the performance advantage possessed by the Bulldog was marginal, Gloster encouraged Folland to continue development of the SS.18 as a company funded private venture.

gladiator zd 6