Bristol Freighter

https://en.wikipedia.org/wiki/Bristol_Freighter

The Bristol Type 170 Freighter was a British twin-engine aircraft designed and
built by the Bristol Aeroplane Company as both a freighter and airliner. Its
best known use was as an air ferry to carry cars and their passengers over
relatively short distances. A passenger-only version was also produced, known as
the Wayfarer.

The Freighter was developed during the Second World War, having attracted
official attention from the British Air Ministry, which sought the development
of a rugged vehicle capable of carrying various cargoes, including a 3-ton
truck. Accordingly, various changed to the design were made to accommodate their
requirements. Being completed too late to participate in the conflict, the
majority of sales of the Freighter were to commercial operators instead. In
response to customer demand, an enlarged version to maximise vehicle-carrying
capacity, known as the Bristol Superfreighter, was subsequently developed.

The Bristol Type 170 Freighter was a twin-engine, high-mounted wing monoplane
that was developed specifically for the purpose of the economic carriage of
freight by air. It was a visually distinctive aircraft, possessing a 'boxy'
fuselage, rounded nose, and a high-set flight deck. In order to maximise the
economical performance of the Freighter, compromises were implemented on other
aspects of performance, resulting in a relatively low cruising speed; this was
not viewed as being of importance to the role of a freighter and thus not a
major diminishing factor. According to aviation publication Flight, the
economics of the Freighter were judged to be a major factor of its market
appeal, as well as the wider economic situation of the United Kingdom at this
time.

Operationally, the Freighter was intended to be employed upon high-frequency
short distance routes as opposed to long-haul routes. Being flown at the low
speeds and short ranges for which the aircraft was intended, the fuel economy
improvements that would be provided by a retractable undercarriage was
outweighed by the increase in structural weight; therefore, it was decided that
a fixed undercarriage would be used, which also had the benefits of reduced
production and maintenance costs. The combination of a high-mounted wing and
fixed undercarriage was considered to be atypical for the era, and resulted in
greater drag than a low-mounted counterpart would have. The main gear legs,
which featured Dowty-built shock absorbers, were supported by an arrangement of
strengthened vertical struts, positioned beneath the aircraft's engines and
horizontally from the lower edge of the fuselage.

The lower nose of the Freighter was covered by a pair of large clamshell doors,
which facilitated easy access to the main hold for loading/unloading payloads;
as a direct consequence of this arrangement, the unpressurised fuselage was
somewhat breezy during flight. The doors, which are hinged outwards, led into a
main hold that had an internal volume of 2,020 cu ft; it was capable of being
loaded with heavy payloads, up to a maximum of 350 cu ft per ton. To better
facilitate loading operations, a built-in hoist is installed upon the fixed
upper surface of the nose, which lowered the requirement for the use of
airport-based infrastructure. Fixed restraining points are present throughout
the internal space in order to secure payloads. On the passenger-carrying
Wayfarer variant, the nose-mounted doors was substituted for by a fixed shell
and the internal volume immediately behind would be used either as a cargo hold
or galley area.

Role
Cargo aircraft

Manufacturer
Bristol Aeroplane Company

First flight
2 December 1945

Introduction
1946

Status
Retired

Primary user
Silver City Airways

Produced
1945 - 1958

Number built
214

Variants
Bristol Superfreighter

On 30 April 1946, the second prototype, which was also the first 34-seat
Wayfarer, registered G-AGVB, made its first flight. It quickly commenced proving
flights in the colours of Channel Islands Airways, where it carried in excess of
10,000 passengers across the span of six months. The third aircraft, registered
G-AGVC, was the first Freighter I and had fully operational nose doors. After a
number of demonstration flights around the world, the Bristol 170 entered full
production. One of the first sales was to the Argentine Air Force, which ordered
15 aircraft.

In military service, Bristol Freighters were operated by the air forces of
Argentina, Australia, Burma, Canada, Iraq, Pakistan and New Zealand. Bristol
Freighters were operated briefly by the Pakistan Air Force. After withdrawal,
some of the Pakistan aircraft were bought by SAFE Air and used in New Zealand.
The Royal Canadian Air Force used five Freighters to carry spares and supplies
between the United Kingdom and their bases in France and West Germany.

The Royal New Zealand Air Force ordered 12 Mk 31M Freighters in the late 1940s.
RNZAF Freighters ranged as far as supplying the New Zealand Army in Malaya, the
British High Commissions (and other support staff) in the Maldives, Ceylon,
India and Nepal, performing Far East Air Force tasks in Malaya (often when other
aircraft types were unserviceable owing to maintenance problems) and Hong Kong.
They ran a highly reliable military shuttle service for allies in Thailand
during the Vietnam War and served several other roles, being adapted for—amongst
other things—aerial top dressing experiments, although to avoid competition with
private enterprise, the New Zealand government did not use them in that role.

Specifications (Freighter Mk 32)

General characteristics
Crew: two
Length: 73 ft 4 in (22.4 m)
Wingspan: 108 ft 0 in (32.92 m)
Height: 25 ft 0 in (7.62 m)
Wing area: 1487 ft2 (138.13 m2)
Empty weight: 29,950 lb (13,404 kg)
Gross weight: 44,000 lb (19,958 kg)
Powerplant: 2 × Bristol Hercules 734 14-cylinder sleeve-valve radial piston
engine, 1,980 hp (1,476 kW) each

Performance
Maximum speed: 225 mph (362 km/h)
Range: 820 miles (1,320 km)
Service ceiling: 24,500 ft (7,470 m)






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