Aeroplane September 2017

AEROPLANE SEPTEMBER 2017 http://www.aeroplanemonthly.com 45

and although some in the airline

were wondering how quickly a new

subsonic jet would become obsolete,

others saw a need for something to

carry the bulk of the traffi c.

A confi dential study dated

March 1965 contained details of

three projected double-deck VC10

developments designated the 300

series. The key driving force was said

to be the need for seat-mile costs 20

to 25 per cent lower than those of the

Boeing 707-320B.

Projected capacity was now for

300 economy-class passengers on the

London or Paris to New York route.

BAC’s market research had indicated

that airlines operating on this route

“would need aircraft with just under

twice their current passenger-carrying

capacity within the next fi ve to seven

years.”

The earlier double-bubble cross-

section had now been superseded

by a faired-in oval with six-abreast

seating on the upper deck and fi ve on

the lower. Interior width was 130in

(330.2cm) with 86in (218.4cm)

headroom on the upper deck and

Flight reported

that BOAC and BAC

felt a double-decker

could make a big

impact on the trans-

Atlantic market

81in (205.7cm) on the lower. Overall

fuselage width was 156in (396.2cm).

Around 24 different confi gurations

and engine types had been evaluated,

from which three were selected for

further study. They shared the same

basic fuselage and wing. They varied

mainly in the location of the RB178

engines, although

there were some

minor differences

in seating

capacity.

All three had

a lower cabin

bisected by the

wing structure.

This provided

a front section

seating 50-70

passengers and a rear saloon for 30-

45, depending on the seat pitch. Top

deck capacity was 191-195.

The 300R featured rear-mounted

engines, while the 300 U/W had

its power units mounted under the

wings. The 300 A/F — standing for

aft fan — had three rear-mounted

powerplants comprising RB178 cores

mated to larger fans. The middle unit

would have been positioned in the

rear fuselage Trident-style.

The key advantage would have

been the saving in weight from

having three engines rather than four

and therefore burning less fuel. At

this stage, before the arrival of the

Douglas DC-10

and Lockheed

TriStar, BAC

engineers were

uneasy about

selling the idea of

a three-engined

long-range

airliner for use

on over-water

routes and one,

moreover, using

unproven powerplants. Specifying

four such units would have got

around most of these objections but

would have created “almost insoluble

installation problems”. The tri-

jet’s advantages were great, but the

engineers realised a lot of research

would be necessary before such an

aircraft could become reality.

38-47_AM_VICKERS_Sept17_cc C.indd 45 31/07/2017 13:28