Blackburn Beverley
The Blackburn B-101 Beverley is a heavy transport aircraft produced by the British aircraft manufacturer Blackburn Aircraft. It was notably the only land-based transport aeroplane built by Blackburn, a company that otherwise specialised in producing naval fighter aircraft.
The Beverley was originally designed by General Aircraft as the GAL.60 Universal Freighter, reflecting its intended use by both military and civil operators. The design process had started during the Second World War, and drew upon the General Aircraft Hamilcar glider. A major design study was conducted in 1945, ahead of Specification C.3/46 being released by the Air Ministry. The company's proposal was accepted and the Air Ministry placed an order for one prototype. General Aircraft was absorbed by Blackburn during the late 1940s, who continued the project. On 20 June 1950, the first prototype conducted its maiden flight from the company's Brough facility; it was Britain's second largest landplane at the time of the flight.
The Ministry of Supply mandated specification changes during the flight test programme, which necessitated a second prototype be constructed to a modified design. On 1 October 1952, an initial order for 20 aircraft was placed on behalf of the Royal Air Force. On 12 March 1956, the first production Beverley C.1 was delivered to No. 47 Squadron, stationed at RAF Abingdon. Between 1956 and 1967, the Beverley would be flown by six squadrons of the Royal Air Force Transport Command. With the RAF, the Beverley would be deployed to various corners of the globe, including Kenya, Bahrain, and Vietnam. Despite ambitions to secure commercial customers for the type, Blackburn were unable to garner orders beyond those placed by the RAF. The final operational Beverley was withdrawn from RAF service during August 1967.
Development
Background
The origins of the Beverley can be traced back to the British aviation company General Aircraft; their chief designer F. F. Crocombe worked on the concept as early as 1939. It had been envisaged that, in light of the intense demands of the Second World War, large aircraft designed specifically for transporting bulky payloads would be immediately attractive to military planners. Furthermore, it was reasoned that such an aircraft would also have a future on the civilian market. It was to be capable of operating as a strategic transport, moving materials and personnel between theatres, and as a tactical transport, deploying straight to the front lines, as well. A greater understanding of tactical transport requirements was gained from wartime experiences, particularly in producing the General Aircraft Hamilcar; these experiences fed into a design study that was completed in 1945.An early configuration for the transporter was of a twin-finned, four-engined, fixed undercarriage, pod-and-boom aircraft that had a detachable compartment. This compartment, which heavily resembled the fuselage of the Hamilcar, was intended to be dropped while the aircraft was flown at a very low altitude to land on its own tracked undercarriage. In 1945, it was proposed for the aircraft to be powered by four Rolls-Royce Merlin engines, capable of carrying a payload of 20,000lb, and having an all-up weight of 75,000lb. Several other configurations were studied, including both twin-engined and four-engined arrangements. An alternative powerplant arrangement of four Bristol Hercules radial engines was also examined. Fixed freight compartments were also present. An enlarged design, powered by four Bristol Centaurus engines, carrying a 38,000lb payload, and possessing an all-up weight of 126,000lb, was produced; this was the closest subject of the design study to what would become the Beverley.
During the late 1940s, the Air Ministry issued Specification C.3/46, which sought a medium-range tactical transport aircraft that would, amongst other criteria, have a payload capacity of 25,000lb, a service ceiling of 18,000ft, and be suitable for missions such as air-dropping paratroops, casualty evacuation, glider towing, and the air-dropping of heavy payloads. The project was boosted by Bristol Aeroplane Company's agreement to develop a version of the Centaurus engine with a two-speed supercharger, capable of producing up to 1,950 hp. General Aircraft were issued with a prototype order from the Air Ministry, the company came to refer to the project as the GAL.60 Universal Freighter to reflect its intended use by both military and civil operators.
Into flight
Construction of the first prototype was undertaken at General Aircraft's Feltham, Middlesex factory. Following the company's merger into Blackburn Aircraft, it was agreed that construction would continue at Feltham, but that, due to the unsuitability of the adjacent Hanworth Aerodrome, it would be disassembled and transported by road to Blackburn's facility in Brough, Yorkshire, where it was reassembled. On 20 June 1950, the first prototype conducted its maiden flight, piloted by chief test pilot Harold Tim Wood; the flight was reportedly trouble-free. At the time of the flight, it was Britain's second largest landplane.Within four weeks of first flying, the first prototype had flown 21 flights and completed all preliminary handling, performance, and load tests. In September 1950, it was first exhibited to the public at the Farnborough Airshow, where an order for a second prototype was announced. Thereafter, it was flown to RAF Boscombe Down for evaluation by the Aeroplane and Armament Experimental Establishment; handling trials were successfully completed within a relatively short period of three weeks. The prototype participated in competitive trials against an American Fairchild C-82 Packet. It also demonstrated its ability to transport heavy loads, including a 30-seat coach and a ten-ton excavator.
The first prototype was promptly followed by a second, which was designated GAL.65 to signify the modifications made from the original design. These changes were largely necessary due to specification revisions by the Ministry of Supply, which sought an increased all-up weight of 127,000lb, and the ability to carry up to 50,000lb payloads over short distances. Amongst the design changes were the substitution of the door-and-ramp combination present at the rear of the aircraft in favour of clamshell doors, while the tailplane boom received seating for 36 passengers. The Bristol Hercules radial engines of the first prototype were replaced with the newer Bristol Centaurus engines, which were furnished with reversible-pitch propellers; this arrangement led to the aircraft having a relatively short landing distance as well as the ability to reverse under its own power. The takeoff and landing distances with maximum load were.
On 14 June 1953, the second prototype performed its first flight. It participated in various trials, including a demonstration air drop over an Army drop zone in Amesbury. Following the completion of testing, it was returned to Brough to be rebuilt into a production standard aircraft.
Into production
On 1 October 1952, an initial order for 20 aircraft was placed on behalf of the Royal Air Force, which designated it as the Beverley C.1. The name Beverley was officially given to the aircraft in December 1952. To accelerate production, Blackburn had several of the aircraft's subassemblies, including the accessory bays, undercarriage systems, and the clamshell doors, manufactured at the works in Dumbarton. Further orders were subsequently received by Blackburn, including for nine aircraft on 30 July 1954, eight more on 2 January 1956, and another ten aircraft were ordered on 24 September 1956, for a total order of 47 aircraft. All of the production Beverleys would be constructed at Blackburn's Brough facility.Several production aircraft participated in evaluations and test programmes. Amongst these were its tropical trials, conducted in North Africa in the summer of 1955, and its winter trials, conducted in Canada during late 1955 and early 1956. In December 1956, the first production Beverley performed a rocket-assisted take off during short take off trials. On 23 April 1953, the Beverley received its certificate of airworthiness.
A total of 49 aircraft were produced, with the last Beverly being completed during 1958. Various proposals were studied by Blackburn for refined or reconfigured variants of the aircraft, but no other customers were ever secured for the Beverly. One specific customer that Blackburn had pursued in the civil sector was Silver City Airways. It was envisaged that the aircraft would be operated as a cross-Channel car ferry, capable of carrying up to six cars and five motorcycles along with 42 passengers. Other initiatives focused on civil freighter operators, with particular efforts being made in the Middle East, including demonstrations involving the air-delivery of materials for the oil extraction industry.
Design
The Blackburn Beverley was a large transport aircraft, designed for carrying large and bulky payloads and landing on rough or imperfect runways, or dirt strips. In terms of its basic configuration, it was a high-wing cantilever monoplane with a fixed undercarriage. The engines and associated accessories were installed in easily interchangeable bays on the lower surface of the wing. The twin-spar wings comprised two separate sections that were bolted onto the fuselage. Simplicity and maintainability were key focus points of its design, thus the Beverley deliberately lacked both pneumatics or cabin pressurisation. The fuselage was divided into four main sections. The aircraft's exterior surface was primarily composed of rivetted Alclad plating. Relatively large low-pressure Dunlop tyres were fitted to the single-wheel undercarriage, which reportedly gave a similar wheel loading to the much smaller Douglas DC-3.The fuselage directly attached to the tailboom and its large rectangular twin-fin tailplane. The cantilever tail surfaces were all-metal and featured a dihedral to keep them clear of the inboard engine's slipstream. The tailboom permitted access to the rear of the fuselage through removable clamshell doors. A device called an Elephant's Foot could be fitted under the centre of the fuselage just forward of the clamshell doors when loading heavy items to prevent the aircraft from tipping back. The flight deck was positioned relatively high, and was accessed via a ladder in the forward portion of the hold. It accommodated two pilots seated in a side-by-side arrangement, who had favourable downwards visibility due to the shaping of the nose; behind them were the navigator and radio operator, seated back-to-back on bench-style seating. All of the flight controls were hydraulically-augmented to reduce pilot fatigue, although manual reversion was possible.
A 36 ft rectangular main fuselage space was supplemented by passenger accommodation in the tailboom. The main cargo hold had a volume of about 6,000 ft3, which could accommodate 94 troops, with another 36 in the tailboom. The floor, composed of light alloy, was corrugated and stressed to take distributed loads of 325lb per square foot. Various payloads could be carried, including numerous vehicles. In one configuration, a maximum of nine Jeep-style road vehicles could be carried, a single fully-fuelled bulldozer could also be transported. Paratroopers in the upper passenger area jumped through a hatch in the base of the boom just in front of the leading edge of the tailplane; paratroopers were also able to exit the cargo hold through the side doors. The Beverley was equipped with toilets, which were situated in the tail beyond the paratroop hatch located on the floor of the tailboom. Following a fatal incident where a serviceman fell twenty feet to the ground while exiting the toilet, unaware that the paratroop hatch had been opened, modifications were made to prevent the toilet doors from being opened while the paratroop hatch was open.