Handley Page Heyford

The Handley Page Heyford was a twin-engine British biplane bomber of the 1930s. Although it had a short service life, it equipped several squadrons of the RAF as one of the most important British bombers of the mid-1930s, and was the last biplane heavy bomber to serve with the RAF. The first aircraft of the type were deployed at RAF Upper Heyford, near Bicester in Oxfordshire.

HP.50 Heyford
Role Heavy night bomber
Manufacturer Handley Page Aircraft
Designer George Rudolph Volkert
First flight 12 June 1930
Introduction 1934
Retired 1941[1]
Primary user Royal Air Force
Produced 1933 - 1936
Number built 125

Design and development

The Heyford was built to meet Air Ministry specification B.19/27 for a heavy night bomber to replace the Vickers Virginia, which required a twin-engined aircraft capable of carrying 1,546 lb (700 kg) of bombs and flying 920 miles at 115 mph (185 km/h).[2] The specification resulted in a large number of proposals being submitted by the British aircraft industry, with designs by Fairey (the Fairey Hendon) and Vickers (the Type 150 and Type 163 being built) as well as Handley Page's design.[3] The prototype, the Handley Page HP.38, was designed by Handley Page's lead designer G. R. Volkert and first flew on 12 June 1930 at Handley Page's factory at Radlett,[4] powered by two 525 hp (390 kW) Rolls-Royce Kestrel II engines driving two-blade propellers.

The aircraft was of mixed construction having fabric-covered, two-bay metal-frame wings,[5] while the fuselage had an aluminium monocoque forward section with a fabric-covered frame to the rear,[6] It had a crew of four, consisting of a pilot, a bomb aimer/navigator/gunner, a radio operator and a dorsal/ventral gunner. Open positions were provided for the pilot and both the nose and dorsal gunners.[6] The Heyford had a novel configuration, with the fuselage attached to the upper wing — somewhat like the 1914-designed German Gotha G.I — and with the bomb bay in the thickened centre lower wing. This provided a good defensive field of fire for the nose and dorsal guns as well as the ventral retractable "dustbin" turret,[7] each equipped with a single .303 in (7.7 mm) Lewis Gun.[4] The fixed undercarriage consisted of large, spat-covered wheels. The design allowed ground crews to safely attach bombs while the engines were running, but the result was that the pilot was some 17 ft (5 m) off the ground.

The HP.38 proved successful during service trials at Martlesham Heath and with No. 10 Squadron RAF and was chosen as the winner of the B19/27 competition, being ordered as the HP.50 Heyford. Production Heyford Is were fitted with 575 hp (429 kW) Kestrel III engines and retained the two-blade propellers, while the IAs had four-blade propellers. Engine variations marked the main Mk II and III differences; the former being equipped with 640 hp (480 kW) Kestrel IVs, supercharged to 695 hp (518 kW) in the Heyford III.

Operational history
A Heyford of 102 Squadron at RAF Honington, 1938

The Heyford I entered service with No. 99 Squadron RAF, at RAF Upper Heyford in November 1933,[8] and later with No. 10 Squadron and 7 Squadron, re-equipping with the Heyford IA and II in August 1934 and April 1935 respectively.[9] As part of the RAF's expansion scheme, orders were placed for 70 Heyford IIIs in 1936, with steam condenser-cooled Rolls-Royce Kestrel VI engines. The delivery of these aircraft allowed the RAF to have nine operational Heyford Squadrons by the end of 1936.[10][11]

These squadrons of Heyfords formed the major part of Bomber Command's night bomber strength in the late 1930s. Heyfords flew many long night exercises, sometimes flying mock attacks against targets in France. Disaster struck on one of these long-range exercises on 12 December 1936, when a flight of seven Heyfords of No. 102 Squadron RAF, flying from Northern Ireland, encountered fog and icy weather conditions as they approached their base at RAF Finningley, Yorkshire. Four crashed and two had to make forced landings resulting in three crewmen killed and three injured.[8]

The Heyford started to be replaced in 1937, with the arrival in service of Armstrong Whitworth Whitleys and Vickers Wellesleys,[12] finally being retired from frontline service in 1939. Some remained flying until 1940 as bombing and gunnery trainers, being declared obsolete in July 1939,[13] with two used as glider tugs until April 1941.[1] At least two examples found experimental use; one for airborne radar and the other for inflight refuelling,[14] and it is reported that one was still stored as late as 1944.[1]

Variants
Heyford I
Powered by 575 hp (429 kW) Rolls-Royce Kestrel III engines: 15 built, serial numbers K3489-K3902 (last aircraft built as Mk.II prototype).
Heyford IA
Engine support changes, power-driven generator, four-blade propellers: 23 built, serial numbers K4021-K4043.
Heyford II
Powered by 640 hp (480 kW) Kestrel IV engines: 16 built, serial numbers K4863-K4878.
Heyford III
Supercharged 695 hp (518 kW) Kestrel VI engines: 70 built in two batches, serial numbers K5180-K5199 and K6857-K6906.

For a total of 125 (including the prototype, J9130)

Operators
 United Kingdom

Survivors

No aircraft, or significant parts from one, survive. The Royal Air Force Museum has some Heyford components: a pair of main wheels, two blades of a Heyford propeller and tailplane parts of Heyford III, K6875 of 166 squadron, recovered from its crash site in the Peak District.[16]

Specifications (Heyford IA)

Data from Aircraft of the Royal Air Force 1918–57[12]

General characteristics

  • Crew: 4 (pilot, co-pilot/navigator, bomb aimer/air gunner, wireless operator/air gunner)
  • Length: 58 ft (18 m)
  • Wingspan: 75 ft (23 m)
  • Height: 17 ft 6 in (5.33 m)
  • Wing area: 1,470 sq ft (137 m2)
  • Empty weight: 9,200 lb (4,173 kg)
  • Gross weight: 16,900 lb (7,666 kg)
  • Powerplant: 2 × Rolls-Royce Kestrel II-S V-12 liquid-cooled piston engines, 525 hp (391 kW) each
  • Propellers: 4-bladed fixed-pitch propellers

Performance

  • Maximum speed: 142 mph (229 km/h, 123 kn) at 13,000 ft (3,962 m)
  • Range: 920 mi (1,480 km, 800 nmi)
  • Service ceiling: 21,000 ft (6,400 m)
  • Time to altitude: 10,000 ft (3,048 m) in 15 minutes 18 seconds

Armament

  • Guns: 3 × .303 in (7.7 mm) Lewis guns (nose, dorsal and ventral 'dustbin' positions)
  • Bombs: 2,500 lb (1,134 kg) total
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See also
  • Avro 613 - an unbuilt competitor for the B.19/27 requirement

Related lists

References
  1. Thetford Aeroplane Monthly February 1996, p. 65.
  2. Barnes 1976, pp. 288, 290.
  3. Jarrett Aeroplane Monthly November 1995, pp. 13–14.
  4. Mason 1994, p.213.
  5. Jarrett Aeroplane Monthly December 1995, pp. 18–19.
  6. Jarrett Aeroplane Monthly December 1995, p. 17.
  7. "New War Plane Has Movable Gun Turret" Popular Science, April 1934, rare photos of dustbin turret at bottom of page 28
  8. Mason 1994, p. 214.
  9. Thetford Aeroplane Monthly January 1996, p. 42.
  10. Mason 1994, p. 215.
  11. Moyes 1976, p. 300: Order of Battle of RAF's Bomber Arm as at 15 December 1936, Group 3.
  12. Thetford 1957, p.246.
  13. Donald, David, ed. The Encyclopedia of World Aircraft. London: Aerospace Publishing, 1997. ISBN 1-85605-375-X.
  14. Jarrett Aeroplane Monthly November 1995, p. 18.
  15. Thetford Aeroplane Monthly February 1996, p. 66.
  16. "Handley Page Heyford - What Do We Have?". Royal Air Force Museum. Retrieved 1 November 2009.

Bibliography
  • Barnes, C. H. Handley Page Aircraft Since 1907. London: Putnam, 1976. ISBN 0-370-00030-7.
  • Barnes, C. H. Handley Page Aircraft Since 1907. London: Putnam & Company, Ltd., 1987.
  • Clayton, Donald C. Handley Page, an Aircraft Album. Shepperton, Surrey, UK: Ian Allan Ltd., 1969. ISBN 0-7110-0094-8.
  • Halley, James J. Royal Air Force Aircraft: K1000 to K9999. Tonbridge, Kent, UK: Air-Britain (Historians) Ltd., 1976. ISBN 0-85130-048-0.
  • Jarrett, Philip. "By Day and By Night: Handley Page Heyford:Part One". Aeroplane Monthly. Vol 23 No 11, November 1995. pp. 12–18. ISSN 0143-7240.
  • Jarrett, Philip. "By Day and By Night: Handley Page Heyford:Part Two". Aeroplane Monthly. Vol 23 No 12, December 1995. pp. 16–21. ISSN 0143-7240.
  • Mason, Francis K. The British Bomber Since 1914. London: Putnam Aeronautical Books, 1994. ISBN 0-85177-861-5.
  • Moyes, Philip J.R. Bomber Squadrons of the RAF and their Aircraft. London: Macdonald and Jane's (Publishers) Ltd., 1964 ( new edition 1976). ISBN 0-354-01027-1.
  • Moyes, Philip J.R. The Handley Page Heyford (Aircraft in Profile number 182). Leatherhead, Surrey, UK: Profile Publications Ltd., 1967.
  • Thetford, Owen. Aircraft of the Royal Air Force 1918-57. London: Putnam, 1st edition, 1957.
  • Thetford, Owen. "By Day and By Night: Handley Page Heyford: Service History:Part One". Aeroplane Monthly. Vol 24 No 1, January 1996. pp. 38–43. ISSN 0143-7240.
  • Thetford, Owen. "By Day and By Night: Handley Page Heyford: Service History:Part Two". Aeroplane Monthly. Vol 24 No 2, February 1996. pp. 62–66. ISSN 0143-7240.
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