104 THE AVIATION HISTORIAN Issue No 21
Two versions of the FC.2 were offered, one non-
pressurised for shorter low-altitude routes and a
pressurised version for high-altitude routes. The
air supply in the latter would be provided by
two Marshall cabin blowers driven by the wing-
mounted engines. The pressurisation system
would maintain ground-level conditions up to
12,500ft (3,870m), after which it would change
progressively up to an altitude of 25,000ft
(7,600m), at which the internal cabin pressure
would be maintained at the normal atmospheric
pressure of 8,000ft (2,400m).
The FC.2 airframe was to be of circular cross-
section and of light-alloy semi-monocoque
construction, combining simplicity of design with
ease of maintenance. The wings and empennage
were to be of orthodox two-spar construction, with
a de-icing system applied to the wings, propellers
and tail unit. The crew was to comprise a pilot,
copilot and radio/navigator, accommodated
in a standardised cockpit with the navigator
located behind the copilot. Two crashproof
fuel tanks were to be installed outboard of the
engine nacelles with another two in the leading
edge of the wings, their combined total capacity
being 950gal (4,319lit). Each engine was sup-
plied by a 15gal (68lit) oil tank.
The FC.2’s mainwheels were to have twin
bogies for reasons of safety. The control surfaces
were to be metal-covered. Rearward-facing seats
offering additional safety could be offered to
prospective customers. Ten oblong clear-vision
passenger windows were to be incorporated,
every alternate window doubling as an escape
hatch. A door in the port rear fuselage provided
easy access to the cabin. A special latch and
hinge arrangement, used in conjunction with
a pneumatic pressure-sealing system, would
allow the door to be jettisoned in an emergency.
Surprisingly, in-flight refuelling equipment was
to be installed as standard, the coupling unit
being installed at the rear end of the fuselage, a
capability then being offered on all airliners being
developed in Britain. In March 1947 detailed
brochures for the FC.2 were prepared and
submitted to the Air Ministry for approval.enter the turboprop
The FC.3 was intended as an alternative to the
FC.2, incorporating two 1,310 e.s.h.p. Armstrong
Siddeley Double Mamba powerplants. These
would be installed on the wings in place of the
Merlins, the nose-mounted engine being deleted.
Fuel capacity was to be 1,155gal (5,250lit) with
4gal (18lit) of oil. The FC.3 would carry the same
number of crew and passengers as the FC.2, the
fuselage aft of the front cabin bulkhead, together
with the wings and empennage, being unaltered.
The forward fuselage would incorporate a
faired nose with an additional section of fuselage
inserted between the flightdeck and the blanked
section of the fuselage. The rear row of seats
was to be omitted and the rear bulkhead moved
forward to close the space.
The Double Mamba comprised two Armstrong
Siddeley Mamba turboprops mounted side-by-
side with a common gearbox containing two
sets of reduction gears to drive, by means of
automatic and hydraulically operated clutches, a
pair of contra-rotating propellers. It was intended
that, once airborne at cruising altitude, one half of
each engine could be shut down to conserve fuel.
In July 1947 a Specification was put to the
International Civil Aviation Organisation (ICAO)
Committee in a joint paper by the Ministry of
Civil Aviation (MoCA) and the Ministry of Supply
(MoS) for a new airliner project. When BOAC
assumed responsibility for all internationalThe FC.3, or Stage II development, was
essentially the FC.2 fitted with a pair
of Armstrong Siddeley Double Mamba
turboprops operating through a common
gearbox and driving contra-rotating
propellers. Fairey had played a major part
in the development of the Double Mamba,
and the powerplant saw extensive service
in Fairey’s Gannet anti-submarine aircraft,
which made its first flight in September 1949.