Avro Anson

Description
The Avro Anson, or ‘Faithful Annie’ as she was affectionately known to many thousands of warttrne and post-war aircrew‘ was one of the most long-lived RAF aircraft‘ having served in various forms for 32 years when it was finally withdrawn 1n l968.

The Anson owed its origin to the Avro 652 six-passenger commercial aircraft ordered in 1934 by lmperial Airways At that time Germany was in the throes of re-arming, and as Britain woke up to the need to counter the growing threat. orders were placed for many new designs of aircraft One pressing need was for a general reconnaissance land-based aircraft to combat the anticipated U-boat menace, and contracts were issued to both Avro and de Havilland, the requirements being later formed into Specification l8/35.

Each firm produced modifications of existing aircraft. The de Havilland entry was K4772, a military version of their semi-obsolescent Dragon Rapide biplane, designated D.H.89M. Avro, however, were able to take advantage of their 652 low-wing monoplane design to produce the 652A, serialled K4771. This made its first flight on 24 March 1935, and was basically similar to its predecessor, but had Armstrong Siddeley Cheetah Vls in place of Cheetah Vs, square windows instead of oval, and suitable military equipment including an Armstrong Whitworth manually-operated upper gun turret ainidships. Tests at Martlesham Heath were followed with comparative trials at Gosport by the Coast Defence Development Unit, the Anson being later involved in a Fleet Exercise in the North Sea, in which it was able to demonstrate its excellent range and endurance. The de Havilland design stood no real chance against its more advanced competitor, and in ]uly l935 the first of many orders was placed, for 174 aircraft, to be named the Anson.

The prototype had not been without its faults, however. When it was tested at Martlesham, criticism was made of its stability and the rudder control, and to counteract this it was fitted with longer tail surfaces, the fin was extended, and the horn balance was removed from the rudder. The Cheetah VI engines were also replaced by Ml<.lXs, these being mounted 3 inches further forward. Following these and other modifications, it was possible to fly the aircraft for lengthy periods without attention. Difficulties with the Centre of Gravity were overcome, avoiding the need to make constant alterations to the trimming gear when passengers moved around. Quicker takeeoffs and slower landings were possible, and the aircraft could now also be SiCl6—S1ipped to some extent. As a result of all the improvements, it was considered possible for the average service pilot to fly the aircraft for lengthy periods without undue strain, and also to carry out cloud ﬂying satisfactorily. This was to prove invaluable for the many roles in which it was destined to serve.

The first production machine, K6152, made its maiden ﬂight at Woodford on 31 December 1935, and when the type entered squadron service three months later it became the first of the new service monoplanes to have a retractable undercarriage. lts row of single square windows had now been converted to a continuous rectangular series of windows on either side, to create what was virtually a glasshouse, giving outstanding visibility to the crew, Retractable wheels were new to the service, however, and several belly landings led to the fitting of a warning horn to remind forgetful pilots that they had failed to lower the undercarriage before closing the throttles. Lowering the landing gear was a tedious manual task on the Anson, requiring 144 turns on a handwheel by the pilot’s seat, a task usually delegated to the navigator or wireless operator‘

Despite its advanced design, the Anson was to be supplanted in the coastal role by Lockheed Hudsons, which had more powerful engines and a greater range. By the time these began to arrive from America, however, shortly before the outbreak of war, the Anson was already serving in what was to be its major role. The possibility of a trainer version had been mooted as early as 1935, and large orders were placed in l939 for this purpose. In the meantime, though, quite a number of the early reconnaissance Ansons had been diverted to training units, pending the arrival of the Airspeed Oxford, which had been specifically designed as a trainer but was not yet available. Flying Training Schools started receiving Ansons for pilot training at the end of 1936, and many more reconnaissance Ansons were later to become trainers in a variety of roles,

The true trainer variant, unlike its predecessor, was fitted with wing flaps and also had modifications to the windscreen, It could be adapted for all types of crew training, and by the outbreak of war was being used at both service and reserve schools for instructing ﬂedgling navigators, air gunners and wireless operators, Those used for gunnery training were equipped with a Bristol hydraulically operated upper turret, fairly similar in design to that of the Blenheim. With the introduction of the British Commonwealth Air Training Plan at the end of 1939, further large orders were placed for machines to be shipped to Canada, Australia, New Zealand, South Africa and Southern Rhodesia, Large numbers were also built in Canada, where the RCAF used different versions of the machine, Canadian-built aircraft fitted with jacobs engines were designated Mkll, whilst Mkslll and IV were British-built machines fitted respectively with jacobs and Wright Whirlwind engines, Later came the Canadian~built MksV and Vl, respectively for navigation and gunnery training, both fitted with Pratt and Whitney Wasp juniors.

One major difficulty with Commonwealth training was that aircrew became accustomed to the clear skies prevalent for much of the year in several of the countries concerned, and had subsequent difficulty adjusting to the British climate, with mountains and high ground often obscured by bad weather‘ To reduce theconsequent high casualty rate, several Advanced Flying Untts were set up around the country‘ those for Observers all being equipped wrth Ansons, the type of aircraft to which they had already become accustomed while training‘

The Anson was used widely by training units in both Bomber and Coastal Commands. A specially equipped version was also used by No 62 Operational Training Units to train radar operators in airborne interception. these being distinguished by an arrowhead-shaped aerial on the nose and a pair of vertical aerials on each wing leading edge. Anson development continued with transport and communications variants. but it was not until after the war that three further modernised trainer versions were produced. All had metal wings and tailplanes. and were fitted with Cheetah XVs. The T20 was built for use as a navigation trainer by the schools being set up in Southern Rhodesia. and was fitted with a transparent nose for bomb—aiming. When tested. however. it met with some criticism. as insufficient space and an inconvenient layout had been provided for trainee navigators. particularly where astronavigation was concerned. and in fact the aircraft was considered unsuitable as an astro or drift platform. Its equivalent for home use was the T.2l, which was ordered in some quantity. whilst a few T.22s were built as radio trainers for air signallers. in all. Over 9.000 Ansons were built by the parent company, in addition to nearly 3.000 constructed in Canada. The last trainer was delivered in 1952. Many surplus machines were civilianised and flown on charter work in the early post-war years.