Vickers Virginia
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The Vickers Virginia biplane bomber was one of the mainstays of the RAF in the interwar years, equipping ten bomber squadrons at its peak, and remaining in front line service from 1924 until 1937. Despite this long service career the Virginia was never a particularly high performance aircraft. Its long lifespan owed much to the limited budget available to the RAF during the 1920s and the slow development of the next generation of heavy bombers at the start of the 1930s.
The Virginia was developed to satisfy an Air Ministry specification for a long distance bomber, first issued in 1920. Vickers responded with an expanded version of the Vickers Vimy, famous for its long range flights in 1919. The new aircraft was a twin engined biplane, with a biplane tail, powered by two Napier Lion engines. It developed through ten different versions over the next ten years, without ever actually reaching the performance called for in the original specification, but during that time it was used as a test bed for a number of new technologies.
Vickers were awarded a contract to produce two prototype Virginias, at the time known as prototype 1 and 2, but now generally referred to as the Virginia I and II. The main production versions were based on the Virginia II, while the Virginia I was repeatedly modified, before both prototypes entered squadron service.
Virginia I
The Virginia I (J6856) had a wooden framework with a fabric covering. It used an enlarged version of the Vimy wing. Both wings were straight, the upper wing was flat and the lower wing had four degrees of dihedral (sloping upwards from the centre to improve stability). It was powered by two Napier Lion engines mounted in flat-sided nacelles and with car type radiators.
The Virginia I made its maiden flight on 24 November 1922. The aircraft was stable, but the rudders needed to be enlarged to make them effective. On 22 December the aircraft was sent to Martlesham for service tests, which continued across 1923.
At the end of these trials the Air Ministry asked Vickers to install two “fighting tops” on the Virginia. These consisted of a pair of nacelles mounted under the upper wing, outboard of the engines. Each of these nacelles carried a gunnery position, which when combined with the nose gun gave the Virginia I five guns. The fighting tops added 1,033lb to the weight of the aircraft, and also added extra drag. Despite further work they were never adopted on production Virginias.
The Vickers I was then used to test the Rolls Royce Condor III engine and a third central rudder. The new engines were delivered in September 1924, and the modified aircraft made its first flight on 3 October 1924. This time rudder control was good, but the aircraft was unstable in flight. This problem was eventually solved by moving the engines forward 25 inches, moving the radiators and adding a fin in front of the third central rudder.
The Vickers I then became the prototype Mk VIII. The rear fuselage was made six feet longer. A new front fuselage was added, both wings were given two and a half degrees of dihedral and the double fighting top was replaced by a smaller single fighting top mounted behind the wings.
J6856 was then turned into a standard Mk VII, with Napier Lion engines and six degrees of sweepback on the main wings. In this form the aircraft was tested by Nos.7 and 10 Squadrons, before in 1928 being rebuilt again as an all metal Mk X. In this form it joined No.7 Squadron as a standard service aircraft, and it was still flying at the end of 1935.
Virginia II
The second prototype (J6857) was completed on 5 April 1924. It was similar to the original version of the Virginia I, but had a new engine installation with close fitting low drag cowling and a semi-circular radiator between the undercarriage legs. One problem revealed in tests on the Virginia I was that the bomb aimers position, just ahead of the nine internally carried bombs, was too cramped. Accordingly the number of bombs carried was reduced to eight, and a new longer nose installed. Finally the tailplane incidence of the Virginia II could be altered in flight. After undergoing trials the Mk II joined No.7 Squadron as a service aircraft. In mid 1927 it was converted to the Mk VII standard, and in 1929 to the all-metal Mk X standard. It was still in service in 1933.
Virginia III
The Virginia III was the first production version of the aircraft. Two were ordered on 23 October 1922, and four more during 1923. The Mk III was similar to the Mk II, but with dual controls. Like the Mk II it could carry eight 112lb bombs internally or two 112lb of 550lb bombs under the wings. It was armed with two guns – one in the nose position and one in a downward firing position in the fuselage. Five of the six Mk IIIs were used to equip No.7 (Bombing) Squadron at Bircham Newton.
Virginia IV
Three Mk IVs were produced. They were similar to the Mk III, but with more electrical equipment, and were able to carry a bigger bomb load. Two entered service, while the third was used to test a third central rudder. This greatly improved directional control, and was introduced on later production aircraft.
Virginia V
The Virginia V was similar to the Mk III, but with the central rudder developed on the Mk IV. Twenty two were built from new.
Virginia VI
The Virginia VI saw two modifications made to the wings. On earlier aircraft the top wing had been flat, while the bottom wing had 4 degrees of dihedral. On the Mk VI both wings had 2.5 degrees of dihedral, improving the stability of the aircraft. The Mk VI also saw the introduction of a new wing folding system. Twenty five Mk VIs were built from new and six were produced by modifying existing Mk Vs.
Virginia VII
The Virginia VII emerged from an attempt to improve the pilot’s visibility. The second prototype Mk III was given a new nose, which also allowed for access between the front gunner and pilot’s compartments. The aircraft was then given the wing dihedral, improving wing folding system and third rudder of the Mk VI, before being used in a series of experiments designed to improve the longitudinal and lateral instability of the aircraft.
A series of tests proved that the aircraft was much more stable if the wings were swept back by 4.9 degrees. The Air Ministry then decided to move the radio operator backwards down the fuselage, and in response the wings had to be swept back even further, to 6 degrees. The fully modified prototype made its first flight on 28 August 1925, and was much more stable than earlier production aircraft. As a result an order followed for eleven new Mk VIIs, while 38 existing aircraft were modified to the new standard.
Virginia VIII
The Virginia VIII was to have been powered by two 650 Rolls-Royce Condor III engines. The original prototype Virginia I was converted to this standard, but no production aircraft followed, and the prototype was soon modified again.
Virginia IX
The Virginia IX was the first version of the aircraft to carry a rear gunner. A new tail plane was developed to compensate for the extra weight, a longer nose was adopted and the radio operator moved back up the fuselage. The new configuration was very popular. Eight Mk IXs were built from new and 27 older aircraft were converted to the new standard. The tail gunner’s position was also installed on the Mk X.
Virginia X
The Virginia X was the final and the most numerous production version of the aircraft, and was the first to feature an entirely metal framework. Early in 1927 Vickers had begun work on a metal framework for the fuselage, working with Virginia VIII J7439, which had suffered damage after flying into the sea. When the Air Ministry asked Vickers to produce metal-framed wings for the Virginia the same aircraft was used. The use of light metal alloys allowed Vickers to produce wings with the same strength as the earlier wooden versions, but that were much lighter. The old wings had weighted 2,300lb, the new ones were 741lb lighter. When combined with the new fuselage 1,100lb of weight was removed from the Virginia. The same aircraft was then given a new all-metal tail unit with all-moving balanced twin-rudders and no fins, which saved more weight and improved the handling of the Virginia.
The prototype aircraft made its maiden flight on May 1927. Tests showed it to have a top speed of 99.5mph at a loaded weight of 17,210lb, a small improvement on the performance of the wooden aircraft. This came at the same time as the RAF announced that it would be focusing on all-metal aircraft.
The production Virginia Xs combined the all-metal construction and new tail of the prototype with the longer nose and tail gunner’s position of the Mk IX. Early aircraft were powered by the Lion VB, but most got the more powerful Lion XI. The lighter metal framework didn’t do much for the speed of the Virginia, but the rate of climb and service ceiling both improved dramatically.
Somewhat ironically the rapid increase in the pace of development of military aircraft at the end of the 1920s and the start of the 1930s gave the Virginia an extra lease of life. In 1927 the Air Ministry issued specification B.19/27, calling for a bomber to replace the Virginia. Over a dozen designs were submitted to this specification (amongst them a Pegasus powered version of the Virginia), but over the next few years the specification had be repeatedly modified to keep up with new fighter aircraft. The contest was won by the Handley Page Heyford (the last big biplane bomber ordered by the RAF) and the Fairey Hendon, but the Heyford did not enter service until 1933, while the Hendon was delayed until 1938!
Even before these delays developed it was clear that the RAF would be without a new bomber for some years, and so in 1928 Vickers received an order for 50 new Virginia Xs. At the same time all existing Virginias were to be rebuilt to the new standard, giving the RAF a total of 102 (or 103) all-metal Virginia Xs. The first of these aircraft were completed in 1930, and were issued to No.500 (County of Kent) and No.502 (Ulster) Squadrons. By the end of 1931 all of the existing Virginia squadrons had the Mk X, and it was then used to equip other existing squadrons, starting with No.10 Squadron in September 1932. At its peak the Virginia X was in service with Nos.7, 9, 10, 51, 58, 75, 214, 500 and 502 Squadrons (although not all at the same time). The peak came in 1936, and by the end of the following year only No.51 Squadron still had the Virginia, replacing it in February 1938.
The Virginia was also the basis of two troop transports – the Victoria, which was developed alongside it, and the Valentia, developed during the 1930s. The Valentia remained in service in the early years of the Second World War.
Stats (Mk X)
Engine: Two Napier Lion VB
Power: 580hp
Crew: 4 – pilot, navigator, two gunners
Wing span: 87ft 8in
Length: 62ft 3in
Height: 18ft 2in
Maximum speed: 108mph at 5,000ft
Empty Weight: 9,650lb
Gross Weight: 17,600lb
Service Ceiling: 15,530ft
Range: 985 miles at 100mph
Armament: One Lewis gun in nose, twin Lewis guns in tail
Bomb load: 3,000lb