Hawker Nimrod
Encyclopedia
The Hawker Nimrod was a British carrier-based
Aircraft carrier
An aircraft carrier is a warship designed with a primary mission of deploying and recovering aircraft, acting as a seagoing airbase. Aircraft carriers thus allow a naval force to project air power worldwide without having to depend on local bases for staging aircraft operations...
single engine, single seat biplane
Biplane
A biplane is a fixed-wing aircraft with two superimposed main wings. The Wright brothers' Wright Flyer used a biplane design, as did most aircraft in the early years of aviation. While a biplane wing structure has a structural advantage, it produces more drag than a similar monoplane wing...
fighter aircraft
Fighter aircraft
A fighter aircraft is a military aircraft designed primarily for air-to-air combat with other aircraft, as opposed to a bomber, which is designed primarily to attack ground targets...
built in the early 1930s by Hawker Aircraft
Hawker Aircraft
Hawker Aircraft Limited was a British aircraft manufacturer responsible for some of the most famous products in British aviation history.-History:...
.
Design and development
In 1926 the Air Ministry specification N.21/6 was intended to produce a successor to the Fairey FlycatcherFairey Flycatcher
-See also:-References:NotesBibliography* Mason, Francis K. The British Fighter since 1912. Annapolis, Maryland, USA: Naval Institute Press, 1992. ISBN 1-55750-082-7.* Taylor, H A. Fairey Aircraft since 1915. London: Putnam, 1974. ISBN 0-370-00065-X....
, then in its fourth year of Naval service. By the time it was replaced by the Nimrod in 1932, the Flycatcher had become so obsolete in terms of its speed that RAF officers who flew it often joked that a sprightly fly might actually give the aircraft a run for its money. None of the aircraft designed to this specification were selected for production after trials in 1928, but the radial engined Hawker Hoopoe
Hawker Hoopoe
-See also:-Bibliography:* Mason, Francis K. Hawker Aircraft since 1920. London: Putnam, 1991. ISBN 0-85177-839-9-External links:*...
, not actually designed to N.21/26, was considered promising enough to be further developed. Despite the Navy's traditional preference for radial engines, Hawker's designer Sydney Camm was convinced by his experience with the landplane Hawker Fury
Hawker Fury
The Hawker Fury was a British biplane fighter aircraft used by the Royal Air Force in the 1930s. It was originally named the Hornet and was the counterpart to the Hawker Hart light bomber.-Design and development:...
that the future for shipborne aircraft also lay with inline engines and began such a design, powered by a Rolls-Royce Kestrel
Rolls-Royce Kestrel
|-See also:-Bibliography:* Erfurth, Helmut. Junkers Ju 87 . Bonn, Germany: Bernard & Graefe Verlag, 2004. ISBN 1-85780-186-5....
. Before it was completed Air Ministry specification 16/30 was written around it. It flew under the initial name Norn early in 1930, received a production contract and was renamed Nimrod.
The Nimrod had an overall similarity with the Fury: it was a single-seater biplane
Biplane
A biplane is a fixed-wing aircraft with two superimposed main wings. The Wright brothers' Wright Flyer used a biplane design, as did most aircraft in the early years of aviation. While a biplane wing structure has a structural advantage, it produces more drag than a similar monoplane wing...
with an open cockpit, fixed undercarriage and guns firing through the propeller. Its unswept, constant chord, round tipped wings had unequal span and strong stagger
Stagger (aviation)
In aviation stagger refers to the horizontal positioning of a biplane, triplane, or multiplane's wings in relation to one another.An aircraft is said to have positive stagger, or simply stagger, when the upper wing is positioned forward of the lower wing, such as the de Havilland Tiger Moth or...
, the latter partly to enhance the pilot's view. It was a single bay biplane braced with outward leaning N-form interplane struts
Strut
A strut is a structural component designed to resist longitudinal compression. Struts provide outwards-facing support in their lengthwise direction, which can be used to keep two other components separate, performing the opposite function of a tie...
, the upper plane held a little above the upper fuselage by cabane struts. The fabric covered wings had metal spars and spruce ribs and carried balanced ailerons only on the upper wings.
The Nimrod's fuselage was a Warren girder structure of tubular steel and aluminium, surrounded by stringers which defined its oval cross section. The Rolls-Royce F.9MS engine, later renamed the Kestrel IIMS was closely cowled in aluminium and the rest of the fuselage fabric covered. As with the Fury, the upper fuselage line was highest at the cockpit, placed between the trailing edges of the upper and lower planes. Its twin machine guns were mounted in the upper fuselage between pilot and engine, firing through the propeller using the standard interrupter gear
Interrupter gear
An interrupter gear is a device used on military aircraft and warships in order to allow them to target opponents without damaging themselves....
. The tailplane was mounted on top of the fuselage and carried split horn balanced elevators
Balanced rudder
The balanced rudder was an innovation in warship construction used as early as 1862 in the USS Monitor, one of the Union's first ironclads during the American Civil War...
; the vertical tail had Hawker's familiar curved shape, with a deep, wide chord, unbalanced rudder
Rudder
A rudder is a device used to steer a ship, boat, submarine, hovercraft, aircraft or other conveyance that moves through a medium . On an aircraft the rudder is used primarily to counter adverse yaw and p-factor and is not the primary control used to turn the airplane...
extending to the keel.
The Nimrod had a conventional undercarriage of cross axle type on trailing struts, with compression legs almost at right angles to the fuselage and a tailskid aft. It could also operate as a floatplane on single step, cross braced floats mounted on N-form struts. With floats fitted the maximum speed was reduced by 47 mph (76 km/h), or 25%. The Kestrel engine's bath type radiator was mounted on the lower fuselage between the undercarriage struts.
After testing in 1930, the prototype went with HMS Eagle
HMS Eagle (1918)
HMS Eagle was an early aircraft carrier of the Royal Navy. Ordered by Chile as the Almirante Cochrane, she was laid down before World War I. In early 1918 she was purchased by Britain for conversion to an aircraft carrier; this work was finished in 1924...
to Buenos Aires
Buenos Aires
Buenos Aires is the capital and largest city of Argentina, and the second-largest metropolitan area in South America, after São Paulo. It is located on the western shore of the estuary of the Río de la Plata, on the southeastern coast of the South American continent...
, flying as part of the British Empire Trade Exhibition there in March 1931. It returned to RAF Martlesham Heath
RAF Martlesham Heath
RAF Martlesham Heath is a former Royal Air Force airfield in England. The field is located 1½ miles SW of Woodbridge, Suffolk.- RFC/RAF prewar use:Martlesham Heath was first used as a Royal Flying Corps airfield during World War I...
for final testing. A production order for 35 was placed and the first of these flew on 31 October 1931. The following year another contract for a further 19 Nimrod Is was signed. With a top speed of 193 mph (311 km/h) it was only marginally slower than its land-based counterpart, the Hawker Fury.
A headrest fairing was added retrospectively to the Nimrod Is, to ease pilot strain during catapult launches. Aircraft from the later production batch were fitted with arrester hooks. Experiments with the first of this batch, refitted with swept upper and lower wings, lead to the Nimrod II. As well as the swept wings, this had at first an uprated Kestrel II engine. Later, these were replaced with Kestrel Vs. Later Nimrod IIs had a slight increase in rudder area to improve spin recovery of inverted, float equipped aircraft. Originally it was intended that the Nimrod II should have a corrosion resistant stainless steel, but only three of these were built. The first of 27/33 Nimrod IIs was delivered in March 1933.
Operational history
The first production Nimrod Is entered service in 1932 with No.408 Flight on HMS Glorious. Others went to No.s 402 and 409 Flights soon after. Fleet Air Arm flights were reorganized into Squadrons early in 1933, with the Nimrods joining No.s 801801 Naval Air Squadron
801 Naval Air Squadron was a Fleet Air Arm squadron of the Royal Navy formed in 1933 which fought in World War II, the Korean War and the Falklands War.- Fleet Air Arm of the Royal Air Force:...
, 802
802 Naval Air Squadron
-Early history:802 Squadron was formed on 3 April 1933 aboard by the merger of two independent RAF naval units, 408 Flight and 409 Flight...
and 803 Squadrons RAF
803 Naval Air Squadron
803 Naval Air Squadron was a Royal Navy Fleet Air Arm squadron.-Interwar:803 NAS was formed on 3 April 1933 by promoting No 409 Flight to the status of a squadron, with nine Ospreys...
.
The Nimrod II followed in September 1934.
Few Nimrods were exported, though one aircraft was supplied to Japan and one to Portugal. Two went to Denmark, where they were known as the Nimrodderne. They were intended as pattern aircraft for proposed licence building and were essentially Nimrod Is, though powered by Kestrel IIIS engines. One, unusually, was fitted with spats.
The Nimrod had been replaced by more modern designs such as the Sea Gladiator
Gloster Gladiator
The Gloster Gladiator was a British-built biplane fighter. It was used by the Royal Air Force and the Royal Navy and was exported to a number of other air forces during the late 1930s. It was the RAF's last biplane fighter aircraft and was rendered obsolete by newer monoplane designs even as it...
by May 1939, before the start of World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
.
Variants
Nimrod I- FAA: 477 hp (356 kW) Rolls-Royce KestrelRolls-Royce Kestrel|-See also:-Bibliography:* Erfurth, Helmut. Junkers Ju 87 . Bonn, Germany: Bernard & Graefe Verlag, 2004. ISBN 1-85780-186-5....
IIMS piston engine; 57 built.
Nimrod II
- FAA: modified swept wing version, powered by a 608 hp (453 kW) Rolls-Royce Kestrel IIS or VFp piston engine; 30 built.
Danish Nimrod
- Hawker built pattern aircraft, powered by a Rolls-Royce Kestrel IIIS piston engine; two built and exported to Denmark.
Nimrodderne
- Single-seat fighter aircraft for the Royal Danish NavyRoyal Danish NavyThe Royal Danish Navy is the sea-based branch of the Danish Defence force. The RDN is mainly responsible for maritime defence and maintaining the sovereignty of Danish, Greenlandic and Faroese territorial waters...
; ten built under licence in Denmark.
AXH1
- A single Hawker Nimrod I supplied to the Imperial Japanese Navy Air ServiceImperial Japanese Navy Air ServiceThe Imperial Japanese Navy Air Service was the air arm of the Imperial Japanese Navy during World War II, the organization was responsible for the operation of naval aircraft and the conduct of aerial warfare in the Pacific War.It was controlled by the Navy Staff of the Imperial Japanese Navy and...
for evaluation in 1934.
Operators
- Marinens FlyvevæsenRoyal Danish NavyThe Royal Danish Navy is the sea-based branch of the Danish Defence force. The RDN is mainly responsible for maritime defence and maintaining the sovereignty of Danish, Greenlandic and Faroese territorial waters...
(Royal Danish Navy Aviation) received 2 aircraft called Nimrødderne. A further 10 were built locally under licence between 1934-35 at Orlogsværftet; called L.B.V (Landbased Biplane 5). The 8 survivors were German spoils of war in 1940.
- Imperial Japanese Army Air ServiceImperial Japanese Army Air ServiceThe , was the land-based aviation force of the Imperial Japanese Army. As with the IJA itself, the IJAAF was developed along the lines of Imperial German Army Aviation so its primary mission was to provide tactical close air support for ground troops while maintaining a limited air interdiction...
received one aircraft, designated AXH.
- Portuguese Air ForcePortuguese Air ForceThe Portuguese Air Force is the air force of Portugal. Formed on July 1, 1952, with the Aeronáutica Militar and Aviação Naval united in a single independent Air Force, it is one of the three branches of the Portuguese Armed Forces and its origins dates back to 1912, when the military aviation...
received one aircraft.
- Fleet Air ArmFleet Air ArmThe Fleet Air Arm is the branch of the British Royal Navy responsible for the operation of naval aircraft. The Fleet Air Arm currently operates the AgustaWestland Merlin, Westland Sea King and Westland Lynx helicopters...
- No.713 Squadron RAF
- No.759 Squadron RAF
- No.780 Squadron RAF
- No.781 Squadron RAF
- No.800 Squadron RAF
- No.801 Squadron RAF801 Naval Air Squadron801 Naval Air Squadron was a Fleet Air Arm squadron of the Royal Navy formed in 1933 which fought in World War II, the Korean War and the Falklands War.- Fleet Air Arm of the Royal Air Force:...
- No.802 Squadron RAF802 Naval Air Squadron-Early history:802 Squadron was formed on 3 April 1933 aboard by the merger of two independent RAF naval units, 408 Flight and 409 Flight...
- No.803 Squadron RAF803 Naval Air Squadron803 Naval Air Squadron was a Royal Navy Fleet Air Arm squadron.-Interwar:803 NAS was formed on 3 April 1933 by promoting No 409 Flight to the status of a squadron, with nine Ospreys...
- 404 (Seaplane) Flight
- 408 (Seaplane) Flight
- No. 1 Flying Training School RAF
Survivors
Two Nimrods survive, both airworthy and both based at the Imperial War MuseumImperial War Museum
Imperial War Museum is a British national museum organisation with branches at five locations in England, three of which are in London. The museum was founded during the First World War in 1917 and intended as a record of the war effort and sacrifice of Britain and her Empire...
's Duxford Aerodrome
Duxford Aerodrome
Duxford Aerodrome is located south of Cambridge, within the Parish of Duxford, Cambridgeshire, England and nearly west of the village.The airfield is owned jointly by the Imperial War Museum and Cambridgeshire County Council and it is the site of the Imperial War Museum Duxford and the American...
, Cambridgeshire
Cambridgeshire
Cambridgeshire is a county in England, bordering Lincolnshire to the north, Norfolk to the northeast, Suffolk to the east, Essex and Hertfordshire to the south, and Bedfordshire and Northamptonshire to the west...
. Both served with No. 802 Squadron
Nimrod I;
- S1581, G-BWWK is operated by The Fighter Collection. It is the fourth production Mk. I, dating from late 1931 and from the first batch built.
Nimrod II;
- K3661, G-BURZ is operated by the Historic Aircraft Collection. It is the penultimate FAA Nimrod, built in early 1934.