General Aircraft Hotspur
Encyclopedia
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The General Aircraft GAL.48 Hotspur was a military glider
Military glider
Military gliders have been used by the military of various countries for carrying troops and heavy equipment to a combat zone, mainly during the Second World War. These engineless aircraft were towed into the air and most of the way to their target by military transport planes, e.g...

 designed and built by the British company General Aircraft Ltd
General Aircraft Limited
General Aircraft Limited was a British aircraft manufacturer from its formation in 1931 to amalgamation with Blackburn Aircraft in 1949 to become Blackburn and General...

 during 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...

. When the British airborne establishment
Airborne forces
Airborne forces are military units, usually light infantry, set up to be moved by aircraft and 'dropped' into battle. Thus they can be placed behind enemy lines, and have an ability to deploy almost anywhere with little warning...

 was formed in 1940 by order of Prime Minister
Prime Minister of the United Kingdom
The Prime Minister of the United Kingdom of Great Britain and Northern Ireland is the Head of Her Majesty's Government in the United Kingdom. The Prime Minister and Cabinet are collectively accountable for their policies and actions to the Sovereign, to Parliament, to their political party and...

 Winston Churchill
Winston Churchill
Sir Winston Leonard Spencer-Churchill, was a predominantly Conservative British politician and statesman known for his leadership of the United Kingdom during the Second World War. He is widely regarded as one of the greatest wartime leaders of the century and served as Prime Minister twice...

, it was decided that gliders would be used to transport airborne troops into battle. General Aircraft Ltd were given a contract by the Ministry of Aircraft Production in June 1940 to design and produce an initial glider for use by the airborne establishment, which resulted in the Hotspur.

Although originally conceived as an "assault" glider which necessitated a compact design, a change in tactical philosophy predicated against the use of small numbers of troops being sent into battle aboard gliders. Due to limitations in its design, the Hotspur was mainly relegated to training where it excelled and became the basic trainer for the glider schools that were formed.

Operational requirements

The German military had pioneered using airborne formations, conducting several successful airborne operations during the Battle of France
Battle of France
In the Second World War, the Battle of France was the German invasion of France and the Low Countries, beginning on 10 May 1940, which ended the Phoney War. The battle consisted of two main operations. In the first, Fall Gelb , German armoured units pushed through the Ardennes, to cut off and...

 in 1940, including the Battle of Fort Eben-Emael
Battle of Fort Eben-Emael
The Battle of Fort Eben-Emael was a battle between Belgian and German forces that took place between 10 May and 11 May 1940, and was part of the Battle of the Netherlands, Battle of Belgium and Fall Gelb, the German invasion of the Low Countries and France...

. Impressed by the success of German airborne operations, the Allied governments decided to form their own airborne formations. This decision would eventually lead to the creation of two British airborne divisions, as well as a number of smaller units. The British airborne establishment began development on 22 June 1940, when the Prime Minister
Prime Minister of the United Kingdom
The Prime Minister of the United Kingdom of Great Britain and Northern Ireland is the Head of Her Majesty's Government in the United Kingdom. The Prime Minister and Cabinet are collectively accountable for their policies and actions to the Sovereign, to Parliament, to their political party and...

, Winston Churchill
Winston Churchill
Sir Winston Leonard Spencer-Churchill, was a predominantly Conservative British politician and statesman known for his leadership of the United Kingdom during the Second World War. He is widely regarded as one of the greatest wartime leaders of the century and served as Prime Minister twice...

, directed the War Office
War Office
The War Office was a department of the British Government, responsible for the administration of the British Army between the 17th century and 1964, when its functions were transferred to the Ministry of Defence...

 in a memorandum to investigate the possibility of creating a corps
Corps
A corps is either a large formation, or an administrative grouping of troops within an armed force with a common function such as Artillery or Signals representing an arm of service...

 of 5,000 parachute troops. When the equipment to be used by the airborne forces was under development, War Office officials decided that gliders would be an integral component, to transport troops and heavy equipment.

On 21 June 1940 the Central Landing Establishment
No.1 Parachute Training School RAF
No.1 Parachute Training School RAF is a Royal Air Force training unit that was initially based at RAF Ringway, now Manchester Airport and is currently based at RAF Brize Norton. It was formed at Ringway on 21 June 1940 as the Central Landing School and from 1 October 1940 it was designated as the...

 was formed at Ringway airfield
RAF Ringway
RAF Ringway, was a Royal Air Force station near Manchester, UK, in the parish of Ringway, then in Cheshire. It was operational from 1939 until 1957.-Prewar years:...

 near Manchester
Manchester
Manchester is a city and metropolitan borough in Greater Manchester, England. According to the Office for National Statistics, the 2010 mid-year population estimate for Manchester was 498,800. Manchester lies within one of the UK's largest metropolitan areas, the metropolitan county of Greater...

; although tasked primarily with training parachute troops, it was also directed to investigate using gliders to transport troops into battle. It had been decided that the Royal Air Force
Royal Air Force
The Royal Air Force is the aerial warfare service branch of the British Armed Forces. Formed on 1 April 1918, it is the oldest independent air force in the world...

 and the Army would cooperate in forming the airborne establishment, and as such Squadron Leader L.A. Strange and Major J.F. Rock were tasked with gathering potential glider pilots and forming a glider unit; this was achieved by searching for members of the armed forces who had pre-war experience of flying gliders, or were interested in learning to do so. The two officers and their newly formed unit were provided with four obsolete Armstrong Whitworth Whitley
Armstrong Whitworth Whitley
The Armstrong Whitworth A.W.38 Whitley was one of three British twin-engine, front line medium bomber types in service with the Royal Air Force at the outbreak of the Second World War...

 bombers and a small number of Tiger Moth
Tiger moth
Tiger moths are moths of the family Arctiidae.Tiger moth may also refer to:*de Havilland Tiger Moth, an aircraft; an aerobatic and trainer tailwheel biplane*de Havilland DH.71 Tiger Moth, an earlier monoplane produced by de Havilland...

 and Avro 504
Avro 504
The Avro 504 was a World War I biplane aircraft made by the Avro aircraft company and under licence by others. Production during the War totalled 8,970 and continued for almost 20 years, making it the most-produced aircraft of any kind that served in World War I, in any military capacity, during...

 biplanes for towing purposes.

As this unit was in the process of being formed, in June the Ministry of Aircraft Production contracted General Aircraft Ltd to design and produce an initial glider type for use by the airborne establishment. It would be used for both assault and training purposes, and would be capable of transporting eight airborne troops. The glider had to be capable of a long approach during landing, due to the prevailing belief at the time that gliders would have to be released a considerable distance from the target and glide in to ensure the sound of the towing aircraft did not alert the enemy. It therefore had to be aerodynamically stable, but also cheap and easy to construct as it would only be used once. The Hotspur was intended to have an operational range of 100 miles (160.9 km) when released at high altitude, although in practice this was reduced to 80 miles (128.7 km) when released from a height of 20000 feet (6,096 m).

Design

The GAL.48 was primarily designed by F.F. Crocombe (team leader) to the Air Ministry specification X.10/40, and was to be similar in design to the German DFS 230 assault glider which had been used in the Battle of the Netherlands
Battle of the Netherlands
The Battle of the Netherlands was part of Case Yellow , the German invasion of the Low Countries and France during World War II. The battle lasted from 10 May 1940 until 14 May 1940 when the main Dutch forces surrendered...

. The first prototype of the glider, designated GAL.48 and which would receive the service name Hotspur Mk I, flew in November, only four months after General Aircraft Ltd had been given the requirement for the glider. An initial order of 400 Hotspurs was placed with General Aircraft Ltd in September by the Ministry of Aircraft Production, nearly two months before the prototype first flew.

The Hotspur Mark I was constructed from wood and was designed to accommodate eight fully armed airborne troops. Its wingspan was 62 feet (18.9 m) and it was 39 foot in length. With a full load (approximately 1880 lbs), it weighed approximately 3600 lbs. The Mk I was distinguished from its other variants by the addition of cabin porthole
Porthole
A porthole is a generally circular, window used on the hull of ships to admit light and air. Porthole is actually an abbreviated term for "port hole window"...

s along its fuselage, and hooks on the nose and tail to allow multiple Hotspurs to be towed together. The two pilots, and later the pilot and instructor when the Hotspurs were used as training gliders, sat in tandem in the cockpit. It had a jettisonable undercarriage, and its unusual fuselage functioned like a lid; once the Hotspur had landed, the troops inside would throw off the top half of the fuselage and then climb out of the lower half, much like leaving a small boat. A total of 18 Hotspur Mk Is were produced, 10 by GAl and eight by Slingsby Aircraft
Slingsby Aviation
Slingsby Aviation is a British aircraft company based in Kirkbymoorside, North Yorkshire, England. The Slingsby business was founded on the building and design of gliders and sailplanes. From the early 1930s to about 1970 it built over 50% of all British club gliders and had success at national and...

.

The first operational Hotspur arrived at the Central Landing Establishment
No.1 Parachute Training School RAF
No.1 Parachute Training School RAF is a Royal Air Force training unit that was initially based at RAF Ringway, now Manchester Airport and is currently based at RAF Brize Norton. It was formed at Ringway on 21 June 1940 as the Central Landing School and from 1 October 1940 it was designated as the...

 between February and April 1941, with 15 being delivered by 22 August. Towing trials began in February 1941 with a Boulton & Paul Overstrand
Boulton Paul Overstrand
-See also:-References:NotesBibliography* Brew, Alec. Boulton Paul Aircraft since 1915. London: Putnam, 1993. ISBN 0-85177-860-7.* Halley, James J. Royal Air Force Aircraft: K1000 to K9999. Tonbridge, Kent, UK: Air-Britain Ltd., 1976. ISBN 0-851330-048-0.* Lewis, Peter. The British Bomber since...

 bomber.

Further development

Even as the initial 400 gliders were being produced, several problems with the Hotspur's design were uncovered, the primary one being that the glider did not carry sufficient troops. Although it had been designed to transport eight airborne troops and a cargo of 1880 lbs, this was found to be inadequate. Tactically it was believed that airborne troops should be landed in groups far larger than eight, and the number of aircraft therefore required to tow the gliders needed to land larger groups would be unfeasible; there were also concerns that the gliders would have to be towed in tandem if used operationally, which would be extremely difficult during nighttime and through cloud formations. Its disappointing glide ratio was also a contributing factor to reevaluate the assault glider concept.

Due to the limitations inherent in the Hotspur design, the decision was made to continue with the development of several other types of gliders, including a 15-seater which would become the Airspeed Horsa
Airspeed Horsa
The Airspeed AS.51 Horsa was a British World War II troop-carrying glider built by Airspeed Limited and subcontractors and used for air assault by British and Allied armed forces...

 and a tank-carrying glider, which would become the General Aircraft Hamilcar
General Aircraft Hamilcar
The General Aircraft Limited GAL. 49 Hamilcar or Hamilcar Mark I was a large British military glider produced during the Second World War, which was designed to carry heavy cargo, such as the Tetrarch or M22 Locust light tank...

. The Hotspur remained in production primarily as a training aircraft and as a "stop-gap" in case the other programmes failed.

Three variants on the original Hotspur Mk I were created. The first was the heavily modified Mk II (Specification X.22/40 and X.23/40), which was redesigned partially to address changes in operational requirements and also to bolster the ground handling of the initial series of aircraft. In operations, rather than releasing the glider from a long distance away and allowing it to glide gently to the ground, it was decided that the towing aircraft would approach the landing zone and only then release the glider, requiring a more robust glider. The Hotspur Mk I wings had also shown considerable flex and the type had proved difficult to handle on the ground. In order to reduce stresses on the airframe, the fuselage was strengthened and wings were "shortened" by over eight ft each, resulting in a wingspan of 45 foot with the tips made square-cut and ailerons moved from the end of the wings to an inset position.

While maintaining its original all-wood construction and overall fuselage and empennage dimensions, the Mk II incorporated a modified fuselage which included altering the cockpit enclosure and a "deeper" canopy. Instead of using the "lid" (where the two pilots still boarded via the hinged Plexiglass canopy), two side doors were added from which troops would enter and depart. The seating was re-arranged, and a braking parachute
Drogue parachute
A drogue parachute is a parachute designed to be deployed from a rapidly moving object in order to slow the object, or to provide control and stability, or as a pilot parachute to deploy a larger parachute...

 added to the rear. Its other dimensions remained the same, however, with a length of 39 foot and a gross weight of approximately 3600 lbs, with eight airborne troops and some 1880 lbs of equipment.

A total of 50 of the early-production Mk IIs were modified into trainers as the Mark III, by adding dual controls and instruments for the student pilot and an externally braced tailplane.

The third variant of the Hotspur was the GAL.48B "Twin Hotspur", which did not progress past the prototype phase. The Twin Hotspur was a 1942 attempt to create a glider capable of carrying 15 airborne troops as an interim glider until production of the Horsa reached sufficient levels. It was created by connecting two Hotspur fuselages together, using a constant-chord centre wing section of 12 feet (3.66 m) length, and a constant-chord tailplane. Two pilots sat tandem-style in the port fuselage. In August 1942, the sole "Twin Hotspur" prototype (MP486) underwent testing, towed behind an Armstrong Whitworth Whitley
Armstrong Whitworth Whitley
The Armstrong Whitworth A.W.38 Whitley was one of three British twin-engine, front line medium bomber types in service with the Royal Air Force at the outbreak of the Second World War...

 tug. The project was abandoned before production could begin, primarily because the glider's flight characteristics were criticised by its pilots.

Production

When Hotspur production ended in early 1943, a total of 1,015 gliders had been produced. The primary sub-contractor, Harris Lebus was responsible for 996 Mk IIs and Mk IIIs while the parent company produced only 10 Mk Is and a single Mk II prototype. Slingsby was the only other sub-contractor involved in production with eight Mk Is completed.

Operational history

Due to changing operational requirements, no Hotspurs were used in combat operations, and were instead exclusively used for training purposes; it was the glider in which all pilots belonging to the Glider Pilot Regiment
Glider Pilot Regiment
The Glider Pilot Regiment was a British airborne forces unit of the Second World War which was responsible for crewing the British Army's military gliders and saw action in the European Theatre of World War II in support of Allied airborne operations...

 received their initial instruction. Although relatively heavy with a high sink rate, the Hotspur exhibited good flying characteristics and could even be flown aerobatically, allowing novice pilots to quickly gain proficiency. The first glider pilots were curiously named "glider coxswains".

Glider pilots first trained at an Elementary Flying Training School on de Havilland Tiger Moth
De Havilland Tiger Moth
The de Havilland DH 82 Tiger Moth is a 1930s biplane designed by Geoffrey de Havilland and was operated by the Royal Air Force and others as a primary trainer. The Tiger Moth remained in service with the RAF until replaced by the de Havilland Chipmunk in 1952, when many of the surplus aircraft...

s or Miles Magister
Miles Magister
-See also:-References:NotesBibliography* Amos, Peter. Miles Aircraft = The early years. Tonbridge: Air-Britain, 2009. ISBN 978 0 85130 410 6...

s before converting to glider training. At the Glider Schools, a Hotspur MK III was first employed for dual instruction with the rear seats weighted for ballast and only the instructor and student aboard. The gliders were usually towed by Hawker Hector
Hawker Hector
-See also:-Bibliography:* Air Transport Auxiliary Ferry Pilots Notes . Elvington, York, UK: Yorkshire Air Museum, 1996. ISBN 0-9512379-8-5....

 or Hawker Audax
Hawker Hart
The Hawker Hart was a British two-seater biplane light bomber of the Royal Air Force , which had a prominent role during the RAF's inter-war period. The Hart was designed during the 1920s by Sydney Camm and built by Hawker Aircraft...

 biplanes (later Miles Master
Miles Master
-See also:-References:NotesBibliography* Amos, Peter and Don Lambert Brown. Miles Aircraft Since 1925, Volume 1. London: Putnam Aeronautical, 2000. ISBN 0-85177-787-0....

 and Westland Lysander
Westland Lysander
The Westland Lysander was a British army co-operation and liaison aircraft produced by Westland Aircraft used immediately before and during the Second World War...

 "tugs") during training. Some 8 to 11 dual-instruction flights usually preceded the student's first solo flight. At Operational Training Glider Schools, the flights were made with troops instead of ballast in Hotspur MK IIs. Release at high altitudes and night-flying was also part of the training.

A total of 250 Hotspurs were retained for operational use if they were required, but the rest were used as training gliders. In 1942, 22 Hotspur Mk IIs were sent to Canada, eventually six were redeployed to the United States Navy
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...

 and one to the United States Army Air Forces
United States Army Air Forces
The United States Army Air Forces was the military aviation arm of the United States of America during and immediately after World War II, and the direct predecessor of the United States Air Force....

. In the build-up to Operation Overlord
Operation Overlord
Operation Overlord was the code name for the Battle of Normandy, the operation that launched the invasion of German-occupied western Europe during World War II by Allied forces. The operation commenced on 6 June 1944 with the Normandy landings...

 in 1944, a scheme was considered in which Hotspurs would have been used to transport cargo and equipment, but this did not get past the planning stage. At war's end, the type was retired and relatively few Hotspurs were preserved for display.

Variants

Hotspur Mk I
Single prototype, production run of 18 aircraft

Hotspur Mk II
Production series, modified with reduced wingspan, inset ailerons, new seating arrangement, deeper cockpit canopy, side doors, braking parachute; fuselage strengthened

Hotspur Mk III
Production series, dual controls and instruments, external tailplane bracing

Twin Hotspur
Two standard Hotspur fuselages and outer wing panels joined together with common centre section and tailplane; single prototype made. This variant did not enter series production.

Operators

  • British Army
    British Army
    The British Army is the land warfare branch of Her Majesty's Armed Forces in the United Kingdom. It came into being with the unification of the Kingdom of England and Scotland into the Kingdom of Great Britain in 1707. The new British Army incorporated Regiments that had already existed in England...

  • Royal Air Force
    Royal Air Force
    The Royal Air Force is the aerial warfare service branch of the British Armed Forces. Formed on 1 April 1918, it is the oldest independent air force in the world...


 Canada
  • Royal Canadian Air Force
    Royal Canadian Air Force
    The history of the Royal Canadian Air Force begins in 1920, when the air force was created as the Canadian Air Force . In 1924 the CAF was renamed the Royal Canadian Air Force and granted royal sanction by King George V. The RCAF existed as an independent service until 1968...


 United States
  • United States Army Air Forces
    United States Army Air Forces
    The United States Army Air Forces was the military aviation arm of the United States of America during and immediately after World War II, and the direct predecessor of the United States Air Force....

  • United States Navy
    United States Navy
    The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...


Survivors

A Hotspur Mark II (HH268) replica is on display at the Museum of Army Flying
Museum of Army Flying
The Museum of Army Flying is an award-winning British military aviation museum about the history of flying in the British Army. It is located beside the Army Air Corps Centre in Middle Wallop, close to Andover in Hampshire, England....

 in Hampshire
Hampshire
Hampshire is a county on the southern coast of England in the United Kingdom. The county town of Hampshire is Winchester, a historic cathedral city that was once the capital of England. Hampshire is notable for housing the original birthplaces of the Royal Navy, British Army, and Royal Air Force...

, England. The front fuselage of a Hotspur was preserved at the Parachute Regiment And Airborne Forces Museum in Aldershot
Aldershot
Aldershot is a town in the English county of Hampshire, located on heathland about southwest of London. The town is administered by Rushmoor Borough Council...

 prior to the museum's 2007 closing, in anticipation of a move to the Imperial War Museum Duxford
Imperial War Museum Duxford
Imperial War Museum Duxford is a branch of the Imperial War Museum near the village of Duxford in Cambridgeshire, England. Britain's largest aviation museum, Duxford houses the museum's large exhibits, including nearly 200 aircraft, military vehicles, artillery and minor naval vessels in seven...

.

Specifications (Hotspur Mk II)


See also


External links

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