The Aviation Historian — January 2018

30 THE AVIATION HISTORIAN Issue No 22

was prepared in the environment created in the

wake of the 1957 Defence White Paper, which

proclaimed that all manned interceptor aircraft

were now obsolete and would be replaced by

surface-to-air guided weapons (SAGW). In

addition, contracts would go only to groups of

companies which were prepared to work together,

the first indication of planned amalgamations of

the various individual aircraft companies that

would follow in 1960.

All design proposals had to be submitted

by January 31, 1958, and brochures or study

reports were forthcoming from Avro, Blackburn,

Bristol, de Havilland, Fairey, English Electric,

Hawker, Handley Page and Vickers-Armstrongs

(Supermarine). Hawker’s proposal was the

P.1129, the final development in a short line of

strike-fighter types which included the P.1121 and

P.1125. Work had started on a prototype P.1121

but it was never completed and the project was

abandoned half-built in 1958, having generated

little interest from potential customers. The

P.1129 was similar to, and essentially an enlarged

version of, the single-seat twin-engined P.1125.

THE CONCEPT

The covering brochure for the P.1129, completed in

January 1958, opens with the following statement:

“Versatility of role is an essential requirement of

any weapon system projected during this present

period, in which the rate of technological progress

is such as to cause premature obsolescence of a

system designed rigidly to a specialist role. The

philosophy underlying the Hawker proposal

is therefore based on the acceptance of this

requirement for versatility, together with a

realistic acknowledgement of the nation’s limited

resources”. Clearly, flexibility of role and a high

performance potential were very necessary, and

the P.1129 offered the following capabilities:

n a 1,000-mile (1,850km) radius, achieved using

overload fuel;

n a level-speed performance of Mach 1·3 (in

fact Mach 1·28) at sea level rising to Mach 2·3

at 36,000ft (11,000m) and above. The maximum

speed with reheat unlit was Mach 1·05 at sea level

and about Mach 1·2 at 36,000ft;

n practicable worldwide operation from 2,000yd

(6,000ft/1,800m) runways in overload condition;

n fighter-type handling characteristics and

strength factors;

n provision for a large variety of weapon loads

including up to eight 1,000lb (454kg) high-

explosive (HE) bombs, and with alternative

specialised packs, including a Q-band radar for

all-weather reconnaissance;

n weapons delivery in toss or diving attacks with

radar-ranging and night display (also to be used

as a flying and navigation aid);

n all-weather navigation based on existing

Doppler and gyro-compass equipment, with the

addition of an X-band sideways-looking radar

and map-reading unit to obtain the necessary all-

weather “fixes”.

The P.1129 satisfied these requirements at a

normal take-off weight of 63,825lb (28,951kg) and

an overload of 79,125lb (35,891kg) when carrying

a crew of two, a Target Marker and 2,250gal

(10,231lit) of fuel internally (in the wings and

three large fuselage tanks). The overload case

ABOVE The P.1129 could trace its roots back to the same company’s P.1121, a strike variant of its P.1103 super-

sonic fighter project to OR.329. A mock-up of the single-seat single-engined P.1121 was built at Kingston, where it

is seen here. The P.1121 was developed into the twin-engined P.1125, which itself led to the larger two-seat P.1129.

TAH ARCHIVE