Select a Flight Magazine report
17 October 1946 - BEA future plans
31 October 1946 - Airscrew turbine progress
14 November 1946 - Todays British transports
21 November 1946 - Brabazon IIA/IIB contenders
28 November 1946 - VC2 first known as Viceroy
7 August 1947 - Viceroy becomes Viscount
20 November 1947 - Introducing the Viscount
22 July 1948 - The Viscounts first flight
1 February 1952 - Tropical trials
1 October 1954 - Britains Big Three
31 December 1954 - Delivery flight of VH-TVA
1 July 1955 - Transair buy Viscounts, + more
9 May 1958 - BEA Viscount 802 loss
Magazine Report
Discover the history of the Viscount with these contemporary reports from the pages of Flight Magazine
Introducing the Viscount
Progress report and brief preliminary description of the Vickers 32-43 seater civil transport
The two large elliptical doors and the large cabin windows are particularly noticeable in
the full-scale mock-up. The mounting for the port inner power unit can also be seen
The outlook - demand - but no supply
It might be unfair to blame anyone in particular for the fact that we have been living in a civil aviation fool's paradise during the last two years. The future looked very different in 1945, and
official plans were made for this future, not for the near-starvation, export-at-any-cost Britain of today. Civil aircraft were laid down for use almost exclusively on our own internal, European,
Empire and trans-Atlantic services.
Whether all these aircraft will be suitable even for this somewhat specialized work remains to be seen, but it is certain that had it not been for the independent decisions of certain individual
manufacturers there would have been none really suitable for the remainder of the world's operators.
At the moment, every airline operator in, the world is either ordering new types or preparing to replace obsolescent types during the course of the next two or three years. Many of them would
prefer to buy British aircraft if we had anything up to date and likely to be available at the right time and of the right size. This we could have had if -------
The position was becoming clear long ago, yet there was no appearance of urgency in the making of new decisions while there was still time. The case of the Ambassador, for instance, has remained
in the pending tray while British European Airways carefully sifted the evidence for and against this type. A decision has now probably been reached, but at the moment of going to press there has
been no official statement. A home order was necessary before the company concerned could go into production with this aircraft — but need the order necessarily have come from BEA? This Corporation
had already spent much time and money on the development of the Vickers Viscount, which was planned exactly to their requirements.
This is as it should be, but why, in the meantime, and knowing the export value of the Ambassador, could not an order have been placed for Transport Command for instance? Means could surely have
been found to get production under way before it was too late, as it will be if the production of the Ambassador is being planned to suit the convenience of BEA, who are not likely to want to start
operating a new aircraft much before 1951.
Of course, production should have been started two years ago or more. This ‘policy’ of building a prototype or two and then waiting for something to turn up is indicative of only one thing — lack of
confidence. Either an aircraft is worth building in numbers for a known market or it is not worth building at all. And if the Ministries do not know what is warned then let the matter be left in
the hands of the aircraft industry, which is familiar with and more at the mercy of the only universal law—that of supply and demand.
Collaboration
Among the reasons often given for America's present lead in civil aircraft, apart from the circumstances of the recent war, is the fact that many, if not most, of her commercial types have been
designed and developed in the very closest co-operation between the manufacturers and the operating companies.
In this country the present muddled set-up has not been calculated to facilitate such close teamwork, a fact which may have had a not inconsiderable influence upon ultimate results. A welcome
proof that the lesson has been taken to heart, and that where there is a will there is a way in spite of obstacles, is afforded by the manner in which the design of the Vickers Viscount has been
tackled.
The British European Airways Corporation has spent large sums of money on the development of the Viking, and to have any hopes of seeing this outlay back, the Viking must remain in operation for
another four or five years at least. This fact has given the Corporation an opportunity to go into great detail in its discussions with Vickers-Armstrongs about the Viscount, and it is probably
true to say that not since de Havilland's designed the Dragon specially for Mr Hillman has a new type been produced in such intimate collaboration between manufacturer and user.
Airscrew-turbine power units are the main uncertainties in the present Viscount plans, but the building of three prototype aircraft, one for each of the units contemplated, should result in
reducing the testing period to a minimum. The three engine firms concerned were also brought into close consultation, so that it does appear that in the Viscount we have an example of cooperation
which deserves to be followed in the future. The result cannot fail to benefit all concerned.
The Viscount
Probably for the first time in this country, a user, one of the English airline operators, has been afforded the opportunity of co-operating to the full, from the beginning, in the design of an
aircraft. Vickers and BEA have set out to build the Viscount as a suitable aircraft for the efficient operation of Continental routes, for a span of operating years starting in three to four
years' time. The Viscount is, therefore, designed as a replacement for the Viking.
The Ministry of Supply originally ordered two prototypes to be powered by airscrew turbines. Vickers-Armstrongs appreciated, however, that there were three possible airscrew turbines which could
be used in an aircraft of the type required; the Rolls-Royce Dart, the Armstrong Siddeley Mamba, and the Napier Naiad, and decided to build a third Viscount as a private venture, so as to provide
a prototype aircraft for each type of engine. The Rolls-Royce Dart has made good progress. It has been run for a thousand hours, and although designed to produce the equivalent of 1,000 hp, it is
capable of development up to 1,400 hp. The Dart and Mamba have both flown on test, in the nose of a Lancastrian, and the Naiad, which is a larger engine designed to provide the equivalent of 1,500
hp, is also progressing.
Mr G R Edwards, the chief designer of Vickers-Armstrongs, decided early on in the design of the Viscount that, since there was to be a choice of three possible types of engines, they should in fact
be as nearly as possible interchangeable.
Such an innovation required similar installation characteristics. He gathered together the engine manufacturers, and between them they decided on a common engine nacelle and structure upon which
could be mounted each type of engine for installation in the Viscount, a development which is not only of technical interest, but one which may prove to be of considerable economic value.
Cockpit
The general cockpit layout is orderly and well planned. The mantelpiece type dashboard
above the instrument panels holds the feathering, fire extinguisher and many other switches.
The more
interesting controls and indicators are shown
1
Torque pressure
7
Pressure system emergency switches
2
Burner pressure
8
Thermal de-icing
3
Oil pressure
9
Fuel flow-metres
4
Cabin ‘height’
10
Cabin pressure unit automatic control panel
5
Nose-wheel steering
11
Ground-setting pressure indicator
6
Inter-com control
12
Miniature Gze
Central Pedestal
A
Push-button control for auto pilot
G
Rudder trim
B
Four high-pressure pump switches and indicators
H
Aileron trim indicator and switch
C
Undercarriage retraction lever
I
SEP1 control panel
D
Four fire-wall fuel cock switches, one cross-feed switch and indicators
K
Power supply changeover switch
E
Emergency undercarriage retraction lever switch and indicator
L
SBA control panel
F
ILS control panel
Early test flights
In about two months the drawings for this new aircraft will be finished, and progress from that moment will depend largely upon the success of the engines in the air, but Rolls-Royce are confident
that the first four Darts will be delivered to Weybridge in time for the Viscount to be completed and ready to fly about midsummer.
The Viscount is not revolutionary in design, and contains many features which are now accepted as normal requirements for passenger-carrying aircraft, but it will certainly be the first British
airline, aircraft to fly which has been designed for airscrew turbines.
Mr Edwards considers that turbines with centrifugal compressors, such as the Dart, are likely to be used operationally before those with axial compressors, since the solution of engine icing and
other problems appear to be much more simple with the centrifugal type. He considers that the use of axial-compressor turbines before such problems are fully solved would seriously prejudice their
future.
Looking aft through the Viscount fuselage. Space beneath the floor
will be taken up with pressurization and de-icing equipment
The fuselage has been designed on the double-curve cross section principle. The wing and fuselage construction follow the same general systems as those on the Viking, but the two types have no
components in common. Whilst making comparison with the Viking, it is interesting to note that the price of the Viscount structure per pound of structure weight is not expected to be more than
slightly above that of the Viking. The ultimate price will depend largely upon the cost of the power units.
Pressure System
As may be seen from this photograph of the aft pressure bulkhead
and fuselage, the first prototype is well under way
The cabin will be pressurized throughout and capable of maintaining an equivalent height of 8,ooo ft when at an actual operating height of 24,000 ft. Vickers have already had considerable experience
of pressurization, having built a hundred Wellingtons with pressurized cabins during the war. The actual system has been designed by Mr J R Leach, of Vickers, but incorporates some components by
outside specialists. Rootes-type blowers are driven by the two starboard and the port inner engines, and after careful routeing the air is fed in through ducts running down the inside of the
fuselage. Combustion heaters are not fitted, but the heat generated by compression of the air by the blowers is used and so controlled that the actual air for pressurization is maintained at the
desired temperature.
From the individual blowers the air passes through silencers, spill and non-return valves. The channels then join and the air passes through a mass-flow metering device to the temperature control
apparatus, which consists of air-to-air heat exchangers, and a turbo-expander refrigeration unit. Air then passes through further silencers into the cabin via either the main low-level ducts or
the head-level punkah louvres. When the main system is not in operation a fan supplies ventilating air through the punkah louvres. Normal extraction is by means of a roof duct which leads to the
lavatories and finally to the main escape valve in the belly of the aircraft.
The pressurization system shown diagrammatically
A
Cabin blowers
J
Electric jack controlling valves and thermostat
B
Safety valve
K
Choke valve and by-pass valve
C
Discharge valve
L
Air distribution ducts in cabin
D
Air silencers
M
Inward relief valve
E
Spill and non-return valves
N
Mass-flow metering duct and control unit
F
Air/air cooler
P
Fan
G
Intercooler for turbo-expander
Q
Non-return valve
H
Thermostatic control
R
Roof ducts
Pressure within the fuselage can be maintained at either ground level up to 15,500ft
actual height, or at 8,000ft up to an actual height of 24,000ft. The graph indicates
the change in cabin
pressure as actual height increases.
Air conditioning on the ground
Units of the temperature-control system are operated automatically by one electric actuator or manually by one lever, so permitting simplified control over the complete temperature range. There is
a specially controlled system for refrigeration and dehumidification, but humidification has not been included since the makers consider it unnecessary. The conditioning system may be put into
operation whilst the aircraft is still on the ground, without running the engines.
Air accidents have demonstrated all too frequently the tendency of modern aircraft, after crashing, to burst into flames due to the rupturing of fuel tanks. The Viscount fuel tanks are of the
flexible crash proof type, and Vickers' own experience of a crash in which these tanks were involved confirms their view that they will successfully withstand impacts which would normally rupture
metal or integral type tanks.
The undercarriage is of the nose-wheel type, and each of the main legs carries two wheels. They retract forwards, in about six seconds. The airframe has been designed to withstand any vertical
gusts which are likely to be met at the operating height, and consequently gust alleviators have not been incorporated.
Safety measures
Anti-icing has been designed on the thermal system. Exhaust gas is collected from the jet pipe of the turbines, mixed with air and passed through the wings and tail unit, the temperature naturally
being controlled.
Double slotted flaps have been included to reduce the landing speed, and provision will be made for reversible airscrews, but the first aircraft will not be so fitted, owing to the already
complicated airscrew controls on turbines, and further development will be necessary before it can in fact be included.
The forward view from pressure cabins is generally rather poor, but Vickers have set out to make the Viscount's view forward at least as good as that on the Viking. To accomplish this, the canopy
has been designed as an excrescence on the natural shape of the fuselage, with the result that despite pressurization, a wider field of view than that of the Viking has been achieved. There is
ample headroom for the pilots both when seated and when standing at the rear of the crew compartment.
Structural details of the Viscount fuselage. Of particular interest is the window-frame construction
Incidentally, the cabin has been fitted with large elliptical windows, which will allow passengers a particularly wide view from their seats. After much study, Vickers found that an elliptical
hole required the smallest weight replacement to make an effective seal for a pressurized fuselage. A single reinforcing member around the hole was found to be adequate.
Interior layout will be similar to that shown in this sectional view of the fuselage
The cabin has been designed to accommodate a Captain pilot, second-pilot navigator, radio officer, and steward. There is no navigation station, but a folding table on the starboard side of the
second pilot's seat is easily brought into position for writing, and the starboard control column can be disconnected. The pantry is amidships in the cabin. A rather neat innovation is the loading
hole in the floor of the pantry to allow loading and unloading of a trolley beneath the aircraft. The automatic pilot is the new Smith SEP1, and standard equipment will include the Instrument
Landing System, and miniature GEE suspended from the roof between the two pilots. Two very large doors, one in the forward position-and one aft (both on the port side) allow quick loading and
off-loading of passengers.
Large, high-backed seats and a new table have been especially designed.
The large windows will provide an excellent view from the cabin
The normal 32-seater version will be known as the Mark I, and a Mark II is already planned providing alternative seating arrangements for 43 passengers. In this model the pantries will be taken
away and a small buffet substituted. The luggage compartment would also be redesigned to accommodate baggage for the extra passengers.
Eighteen months of development flying have been allocated so as to ensure that the Viscount is a workable proposition before it goes into service. That time has been estimated by Mr Edwards as
being necessary for airframe development alone, and is quite apart from any engine development which may be required. He hopes, therefore, that Vickers will be in a position to start a dribble of
production by early 1950. There may be a few machines through before then, however, and he considers that the Viscount will be ready for operation on the routes in 1951.
Viscount Mk.I
Dart
Mamba
Naiad
Take-off weight (lb)
40,350
39,500
40,500
Landing weight (lb)
35,630
34,780
35,780
Take-off weight to clear 50ft (yds)
1,100
1,160
920
Landing distance from 50ft (yds)
860
845
870
Pay load (lb)
7,600
7,615
7,560
Still air range (nautical miles)
700 at 240 knots
700 at 243 knots
825 at 270 knots
Viscount Mk.II (Long range)
Take-off weight
45,000 lb
Landing weight
43,000 lb
Pay load and still-air range (25.000ft at 275 kts)
at 6,180 lb
1,525 nm
at 10,000 lb
880 nm
