Short S.14 Sarafand Flying Boat [1/8] - Short-Sarafand.jpg (1/1)

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By William Pearce

In 1928, H. Oswald Short of Short Brothers envisioned a larger follow-on to his
Singapore II flying boat. He believed that Short Brothers could design and
construct a streamlined flying boat that would be just as large as the 12-engine
Dornier Do X (the largest aircraft at the time) but with better performance.
This new aircraft was designated S.14, and Short Brothers prepared preliminary
drawings to seek funding. After prolonged discussions, Short was able to gain
the support of the British Air Ministry to fund the S.14 under specification
R.6/28.

The Short S.14’s chief designer was Arthur Gouge. The aircraft was a large
biplane flying boat capable of transatlantic service. The S.14’s six engines
were placed between the wings in three tandem pairs, each pair sharing a
streamlined nacelle. A 1/14th scale model was tested in the Royal Aircraft
Establishment’s wind tunnel with satisfactory results, and construction of the
aircraft began in mid-1931.

The equal-span, fabric covered wings were slightly swept. Because of the loads
imposed on the large wings, their spars were made of stainless steel rather than
duralumin (an aluminum alloy that incorporates copper, manganese, and magnesium
for increased hardness). Toward the end of each lower wing was a wing tip float.
The bottoms of the floats were made of stainless steel, but they also had
provisions to mount a replaceable zinc plate. The zinc plate acted as an anode
to prevent corrosion from occurring on the rest of the aircraft.

The upper and lower wings were joined by a series of struts, and the center
struts also supported integral engine nacelles. Two Rolls-Royce Buzzard III
engines were positioned back-to-back in each engine nacelle, and the radiators
for the engines were housed below the engine nacelle. The Buzzard III engine had
a 6.0 in (152 mm) bore, a 6.6 in (168 mm) stroke, and a total displacement of
2,239 cu in (36.7 L). Each of the six engines produced 825 hp (615 kW) at 2,000
rpm and 930 hp (699 kW) at 2,300 rpm. Each engine turned a wooden, fixed-pitch,
two-blade propeller. Each front engine used a 15 ft (4.57 m) diameter propeller,
and each rear engine used a 14 ft (4.27 m) diameter propeller.

The aircraft’s two-step hull was made of duralumin and had a planing bottom made
of stainless steel. A large Flettner servo tab trailed behind and controlled the
S.14’s rudder. The elevators had balancing airfoils on their upper and lower
surfaces. An auxiliary fin was positioned on each side of the horizontal
stabilizer, and their incidence could be altered by the pilot to trim out any
yaw experienced from a dead engine.

The S.14 was given the serial number S1589 and was eventually named the
Sarafand. The aircraft had a wingspan of 120 ft (36.6 m), a length of 89.5 ft
(27.3 m), and a height of 30.3 ft (9.2 m). The upper wing held 2,110 gallons
(7,987 L) of fuel, and the lower wing held 1,272 gallons (4,825 L). Each of the
Sarafand’s six engines had individual tanks for their 28.5 gallons (45.9 L) of
water (for the cooling system) and 16 gallons (25.7 L) of oil. The Sarafand had
an empty weight of 44,740 lb (20,293 kg) and a fully loaded weight of 70,000 lb
(31,752 kg). The aircraft had a 1,450 mi (2,334 km) range and a 13,000 ft (3,962
m) ceiling. The Sarafand’s max speed was 153 mph (246 km/h).

The Sarafand was the world’s second largest aircraft at the time—the Do X
retained its title as the largest. However, the aircraft was never intended as a
commercial transport. The Sarafand was strictly for military use as a possible
long ranger bomber or reconnaissance aircraft. While it is unlikely that guns
were ever installed, the Sarafand did have a number of gun positions: one in the
nose, two behind the wings in the upper fuselage, and one behind the tail. The
aircraft’s crew of ten had ample accommodations in the Sarafand’s interior,
including a ward-room, six folding bunks in various crew rooms, a galley, a
maintenance area, and a lavatory. The crew stations were linked by a telephone
intercom. A section of the upper rear fuselage could be removed to allow a spare
engine to be loaded in the aircraft for transport, and a portable jib was
carried to allow engine changes while the Sarafand was afloat. The pilot and
copilot sat in tandem in a fully enclosed cockpit.

The aircraft was built in Rochester in the Short Brothers’ No. 3 riverside shop,
but the shop was not tall enough to accommodate the Sarafand with its upper
wings in place. As a result, the partially completed aircraft was launched on 15
June 1932 and taken down the River Medway to a shipyard where the upper wings
were attached.

The completed Sarafand was relaunched on 30 June and flown for the first time
later that day with John Parker as pilot and Oswald Short as copilot. Controls
were found to be light and well balanced, and only minor adjustments were
needed. A few other flights were made before the aircraft was demonstrated to
the press on 11 July. For this flight, the Sarafand became airborne in 19
seconds, reached a top speed of around 150 mph (241 km/h), and flew for about 40
minutes.

The aircraft made several additional test flights and was delivered to the
Marine Aircraft Experimental Establishment (MAEE) in Felixstowe on 2 August
1932. The MAEE found the Sarafand to have an excessive takeoff run when heavily
loaded, vibration issues from the tractor and pusher propellers, and a tendency
to porpoise on landing in certain conditions. The MAEE also believed the
aircraft would have cooling issues if it were operated in warmer climates.

In late 1933, the stainless steel planing bottom was found to be corroded and
was replaced with Alclad (corrosion-resistant aluminum sheeting). Further
changes were made to the wing braces and hull to address the vibration and
porpoising issues. The Sarafand was relaunched on 29 April 1934 and continued to
be used for various experimental flights by the MAEE, although it spent much
more time at its mooring than in the air. By 1936, the Sarafand and its biplane
configuration were outdated, and the aircraft was scrapped. The Short S.14
Sarafand was really nothing more than an experimental aircraft that pushed the
limits of aircraft design. It proved to be reliable and easy to fly, and it
helped to pave the way for future large aircraft.




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