in Flightglobal site,there is an artist picture to Supermarine six-engned
flying boat of 1930,who have more info about it?,and for which Spec. it
was designed ?.
This seems very close to the Short Sarafand, especially the proposed monoplane version- even down to the power plant (6 x RR Buzzard), was there some sort of official requirement for a civil flying boat in this class?
A slightly longer answer: according to Bill Gunston in 'Giants of the sky', Oswald Short saw the Do X and thought his company could make an aircraft at two-thirds of the weight with comparable load/range performance. Next, he convinced the government to pay for such an aircraft. Specification R.6/28, which asked for a large reconnaissance aircraft, was written around what was to become the Short Sarafand. The specification was issued to other manufacturers as well, one of them being Supermarine, who designed their type 179. Short received a contract for a reconnaissance aircraft, Supermarine received a contract for a passenger aircraft. Short built and flew one S.14 Sarafand. Supermarine never finished their single type 179; it was cancelled before completion.
Please allow me to clarify the story regarding the Type 179.
Supermarine drew up a six-engine (probably RR Buzzard) monoplane, Type D in Supermarine's old project naming system, to spec. R.6/28 but this was not ordered by the Air Ministry.
The design was enlarged and modified as a civil flying boat, Type 179, powered by six Bristol Jupiters (see posts #5 and #6). One example was ordered by the Ministry to spec 20/28, but with the engines changed back to RR Buzzards (see posts #2 and #9).
The aircraft was then redesigned completely in 1930-1931; most noticeably the elliptical wing was dropped in favour of straight-tapered and eventually the three twin-engine nacelles became two twin-engine and two single engine (see posts #6 and #8)
Thanks a lot Schneiderman for these most valuable explanations.
It has often been said that Supermarine pioneered the elliptical wing design with the Spitfire, and though somewhat exaggerated, this proves the elliptical wing truly was on the company's drawing boards from an early stage.
Its surprising how many aircraft were drawn with elliptical wings in the early stages of design only for this to be dropped in favour of a simpler style later. The lift/drag benefits were not always worth the additional construction costs.
One other reason for not placing the engines on the leading edge was that this was utilised as a condenser for the evaporative cooling system. A further would be that three engines each side places the outer-engines a long way out.
The market for very large flying boats at this point was essentially zero. There was no production order for the Short Sarafand and Dornier's DoX, 3 built, never entered commercial service.