Tuesday 18 June 2013

Vickers Vanguard Turboprop Airliner

 

The Vickers Vanguard was a British short/medium-range turboprop
airliner introduced in 1959 by Vickers-Armstrongs, a development of
their successful Viscount design with considerably more internal room.
The Vanguard was introduced just before the first of the large
jet-powered airliners, and was largely ignored by the market. Only 44
were built, ordered by Trans-Canada Air Lines (TCA) and British
European Airways (BEA).

      After only about 10 years service TCA experimentally converted
one of theirs to a freighter configuration, calling it the Cargoliner.
This was considered successful, and in the early 1970s most were
converted to freighters, those from BEA becoming the Merchantman.
These freighters remained in service for many years, with the last one
(G-APEP) only retiring in 1996.
The very considerable success of the Vickers Viscount in airline
service was due to the smoothness, economy and reliability of its
turbine engines. In one enormous leap it had raised cruising speed
almost 100% by comparison with the piston-engined Vickers Viking; it
carried two or three times as many passengers (according to type) and
offered increased range. In early 1953, not long after the Viscount
entered service with British European Airways (BEA), discussions began
to initiate the design of a successor. Both BEA and Trans-Canada
Airlines were interested in a generally similar aircraft; compromise
in design to satisfy the views of these two operators resulted in the
low-wing configuration and 'double-bubble' fuselage to provide a large
underfloor cargo hold beneath the main cabin.

The power plant considered originally for inclusion in the design was
the Rolls-Royce Dart. But Rolls-Royce intimated that development of a
new engine, the RB.109, was then well under way and it (later known as
the Tyne) was chosen to power this new transport. Construction was
entirely conventional except for the wing, which introduced integrally
machined skins of light alloy to provide spanwise stiffening at low
cost, and three shear webs instead of the single spar in the Viscount
wing. When tied together by closely spaced ribs it produced a rigid
box structure and outboard of the centre-section it was sealed to form
integral fuel tanks.

First flight of the prototype Vanguard, as the new aircraft had been
named, was made on 20 January 1959. But because of the normal
development programme of a new civil airliner - coupled with delays
caused by problems with the new power plant - it was not until 1
February 1961 and 1 March 1961 that these aircraft began regular
service with Trans-Canada Airlines and BEA respectively. By then this
and other second-generation turboprop-powered airliners had been
deposed by the development and introduction into service of economical
turbojet-powered airliners such as the Boeing Model 707. Consequently
production ended after the original orders had been completed: 20 for
BEA and 23 for Trans-Canada Airlines.
On 10 October 1969 the first of nine freighter conversions of the
Vanguard, called Merchantman, was flown for BEA.


Contents:-

1. Design and development
2. Operational history
(a). Cargo operations
3. Accidents and Incidents
4. Specifications (Type 952)
5. Perfomance
6. DIMENSIONS
7. MODEL Type
8. PASSENGERS 97-139
9. WEIGHTS



1.Design and development:-

The aircraft was designed to a BEA requirement for a 100-seat aircraft
to replace their Viscounts. The original Type 870 design was then
modified when TCA expressed their interest in the design as well, and
Vickers returned the updated Type 950 that filled both requirements.
The main difference between the Viscount and Vanguard was the
construction of the fuselage. The Vanguard started with the original
Viscount fuselage, but cut it off about halfway up from the bottom,
replacing the top section with a larger-diameter fuselage to give it a
double bubble cross-section (similar to the Boeing Stratocruiser). The
result of the larger upper portion was a roomier interior, with
increased cargo capacity below the floor.
With this larger, and heavier, fuselage came the need for a new engine
to lift it. Rolls-Royce delivered their new Tyne design with a nominal
4,000 hp/3,000 kW (as compared to the Viscount's Dart of about 1,700
hp/1,300 kW). This allowed for a much higher service ceiling and
cruising speed; the Vanguard had a service ceiling almost twice that
of the Viscount. The Vanguard was one of the fastest turboprops ever
and was faster than the present day Saab 2000 or de Havilland Canada
Dash 8. A [probably hyped] pilot report describes maintaining 10,000
ft altitude with three engines feathered and the port outer at maximum
cruise power; weight at start of that flight was about 112,000 lb.
This is notably better performance than a Lockheed C-130, an aeroplane
of similar weight and power that could not (in its introductory
version of 1957) maintain a constant altitude on a single engine.
Nevertheless, the Vanguard was certainly overpowered.
The first Type 950 prototype G-AOYW flew on 20 January 1959. The
flight, a transfer to Wisley 3 miles away, had been planned for
December but the engines were returned to Rolls-Royce for minor work.
Proper flight testing was then carried out from Wisley.

2.Operational history:-

The Vanguard entered service with BEA and TCA in late 1960. BEA
operated their first Vanguard schedule on 17 December from Heathrow to
Paris. Following delivery of their full fleet of six V951 and 14 V953
aircraft by 30 March 1962, the type took over many of BEA's busier
European and UK trunk routes. The aircraft received names of famous
Royal Navy warships; the first G-APEA was named "Vanguard", but these
tended to be dropped later in service. Initial seating was 18
first-class at the rear and 108 tourist, but this was changed to 139
all-tourist, in which configuration, the Vanguard had very low
operating costs per seat/mile. On flights up to 300 mi (480 km), such
as from London to Paris, Brussels and Amsterdam, the type could match
the block times of the pure jets which were being introduced in the
early 1960s. The remaining BEA fleet passed to British Airways on 1
April 1974 and the last BA passenger flight with the type was on 16
June 1974.
TCA initiated Vanguard schedules on 1 February 1961 with two flights
from Toronto and Montreal via intermediate stops to Vancouver. The
fleet was also used on services from Toronto and Montreal to New York
and Nassau, Bahamas.

2.1.Cargo operations:-

In 1966, Air Canada removed all the seats in CF-TKK and refitted the
aircraft for pure cargo work, in which role it could carry 42,000 lb
(19,050 kg) of freight. Known by the airline as the "Cargoliner," it
was the only such conversion, but survived to be the last Canadian
Vanguard to be retired in December 1972.
BEA operated nine Vanguards modified to the V953C "Merchantman"
all-cargo layout from 1969, with the first two conversions being
designed and carried out by Aviation Traders Engineering Ltd (ATEL) at
Southend Airport. BEA modified the remainder at Heathrow using kits
from ATEL. A large forward cargo door (139 in/353 cm by 80 in/203 cm
high) was incorporated. The Merchantmen continued in service with BA
until late 1979 when the remaining five were sold.
Air Bridge Carriers purchased several of the Merchantmen and operated
them until 1992, when its changed to Hunting Cargo Airlines. Hunting
Cargo operated their last V953C flight on 30 September 1996 and
donated G-APEP to Brooklands Museum on 17 October 1996.

3.Accidents and Incidents:-

1.On 27 October 1965, British European Airways Vickers Vanguard G-APEE
flying from Edinburgh Airport to London Heathrow Airport, during a
landing in poor visibility, attempted an overshoot but crashed on
runway 28R. All on board died, six crew and 30 passengers.
2.On 2 October 1971, British European Airways Flight 706. operated by
Vickers Vanguard G-APEC crashed near Aarsele in Belgium. The cause was
the failure of the rear pressure bulkhead and subsequent destruction
of the tailplane. All eight crew and 55 passengers died.
3.On 10 April 1973, Invicta International Airlines Flight 435,
operated by Vickers Vanguard G-AXOP crashed near Basel-Mulhouse
Airport Switzerland. Four crew and 104 passengers died.
4.On 29 January 1988, Inter Cargo Service Flight 1004, operated by
Vickers Vanguard F-GEJF crashed on takeoff from Toulouse-Blagnac
Airport when takeoff was attempted with only three fully operable
engines.
5.On 6 February 1989, Inter Cargo Service Flight 3132, operated by
Vickers Vanguard F-GEJE crashed on takeoff from Marseille-Marignane
Airport, France. Three crew died; no passengers were carried.

4.Specifications (Type 952):-

General characteristics
Crew: 2-3
Capacity: 139 passengers
Length: 122 ft 10 in (37.50 m)
Wingspan: 118 ft 7 in (36.10 m)
Height: 34 ft 11 in (10.60 m)
Wing area: 1,527 ft² (142 m²)
Empty weight: 82,500 lb (37,421 kg)
Loaded weight: 141,000 lb (63,977 kg)
Powerplant: 4 × Rolls-Royce Tyne RTy.11 Mk 512 turboprop, 5,545 hp
(4,700 shp, 4,135 kW) each.


5.Performance:-

Maximum speed: 425 mph (684 km/h)
Range: 1,830 mi (2,945 km)
Service ceiling: 30,000 ft [15] (9,145 m)
Wing loading: 92 lb/ft² (450 kg/m²)
Power/mass: 0.16 hp/lb (0.26 kW/kg)
Cruise speed 684 km/h 425 mph
Ceiling 9145 m 30000 ft
Range w/max.payload 2945 km 1830 miles


6.DIMENSIONS:-

Wingspan 36.14 m 119 ft 7 in
Length 37.45 m 123 ft 10 in
Height 10.64 m 35 ft 11 in
Wing area 141.86 m2 1526.97 sq ft



7.MODEL Type:-

952 "Vanguard"
CREW 2-3

8.PASSENGERS 97-139

ENGINE 4 x Rolls-Royce Tyne RTy.11 Mk 512 turbo-prop, 4135kW

9.WEIGHTS

Take-off weight 63977 kg 141046 lb
Empty weight 37421 kg 82500 lb


BRITAIN'S NEW TURBOPROP AIRLINER:-

Now a few days' time the first Vickers Vanguard is to make its first
flight.The following pages bring Flight's readers up to date with the
engineering and economic facts about the aircraft. It will be seen
that the Vanguard promises to be a highly efficient tool of the air
transport trade. But good engineering and good economics are not the
only guarantees of acceptance, prerequisite though these two things
may be. The overall design-strategy must be right, otherwise efficient
economics and sound nuts-and-bolts—the "tactical" considerations—may
be academic. What, then, is the strategy behind the Vanguard? There
are five answers to this question. One, the Vanguard is the first
British airliner which can truly claim to possess the star quality of
built-in airline experience—the quality which has ensured Lockheed's
and Douglas's domination of world airline markets to date. The
Vanguard is not—as was the Viscount when it first appeared—just "a
good aeroplane." This is the two-dimensional view of an aeroplane's
suitability for airline use; the third dimension must be added from a
depth of airline operating designexperience. Vickers and Rolls-Royce,
with 350 Viscounts in service, are acknowledged to possess this
experience, and it has all been built into the Vanguard.
Two, the Vanguard sprang from the requirements of a most economically
intransigent kind of air transport—the field of
international short-to-medium stage operations. It can be said without
fear of dissent that a transport designed to master the economics of
intra-European routes is basically master of the denser
short-to-medium stage networks anywhere.Three, the choice of turboprop
propulsion permits the Vanguard to exploit with greater margins of
profit these economically difficult short-to-medium stages. (The
average intra-European sector distance is less than 300 miles.) Such
stages tend to be too short to permit full economic use to be made of
the jet's speed; yet the Vanguard—with a cruising speed of 425 m.p.h.
and above—can offer block speeds which are highly competitive with the
500-550 m.p.h. jets. Such routes are the realm of the Vanguard even in
idealized airtraffic-control conditions. In the practical conditions
of dayto-day operations, in which airliners have to cruise or hold as
they are told, the more fuel-thrifty Vanguard may be a decisive
advantage.Four, the size of the Vanguard is a realistic attempt to
provide a vehicle which can shift annually increasing traffic flows at
a lower specific cost. The Vanguard represents a
breakaway from the past tradition that short-haul airliners are small
and long-haul airliners are big. There is as great a, if not greater,
need on the shorter stages to handle growing traffic
volumes by increased aircraft-size rather than by operating smaller
airliners at increased frequencies. In this way the
Vanguard reduces the specific cost of operation, and fares can be
lowered to produce a "benevolent" generation of more
traffic and a further reduction of specific costs. This is an
important aspect of the Vanguard's strategy, and it is no doubt the
justification for Vickers' claim that the aircraft is capable of
cutting air fares by half. There is, of course, the present limitation
of a fixed fare for all types of aircraft; but there are strong signs
that the inevitable eventual differentiation of price between jets and
propellers will come sooner rather than later. When this happens, the
Vanguard's low-cost capabilities can be exploited to the full. Thus
not only can the aircraft be easily topped up with bulky freight
during off-peak passenger periods, but it can also be regarded as a
realistic answer to the need for positive development of freight.
Hitherto the cargo market has been largely developed by passenger
aircraft, and the Vanguard's design recognizes this fact. For
specialist airfreight operators, however, a full freighter
version—with a 40,000 lb payload—is offered. Five, the Vanguard
uniquely offers the operator a complete solution to one of his biggest
economic problems: the economic unbalance of seasonal-type traffic.
With but small penalties in speed and weight, very large underfloor
freight capacity is available—enough, it is claimed, to permit full
design payload to be carried with but one quarter of the seats filled.
These are the factors which should make the Vanguard not just a good aeroplane, but a good airline aeroplane.
























No comments:

Post a Comment