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1938 De Havilland Tiger Moth DH.82A
N555XB / G-ASXB (sn 3852)
Photo taken July 14, 2007
Arlington Northwest EAA Fly-In July 2007
Arlington, WA USA (KAWO) |
| Photo © Marcel Siegenthaler |
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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 1952 when many of the surplus aircraft entered civil operation. Many other nations used the Tiger Moth in both military and civil applications, and it remains in use as a recreational aircraft. It is still occasionally used as a primary training aircraft, particularly for those pilots wanting to gain experience before moving on to other tailwheel aircraft, although most Tiger Moths have a skid. Many are now employed by various companies offering trial lesson experiences. Those in private hands generally fly far fewer hours and tend to be kept in concours condition. The de Havilland Moth club founded 1975 is now a highly organized owners' association offering technical support and focus for Moth enthusiasts.
Design and development
The Tiger Moth trainer prototype was derived from the DH 60 de Havilland Gipsy Moth in response to Air Ministry specification 13/31 for an ab-initio training aircraft. The main change to the DH Moth series was necessitated by a desire to improve access to the front cockpit since the training requirement specified that the front seat occupant had to be able to escape easily, especially when wearing a parachute. Access to the front cockpit of the Moth predecessors was restricted by the proximity of the aircraft's fuel tank directly above the front cockpit and the rear cabane struts for the upper wing. The solution adopted was to shift the upper wing forward but sweep the wings back to maintain the centre of lift. Other changes included a strengthened structure, fold-down doors on both sides of the cockpit and a revised exhaust system. It was powered by a de Havilland Gipsy III 120 hp engine and first flew on 26 October 1931 with de Havilland Chief Test Pilot Hubert Broad at the controls.
One distinctive characteristic of the Tiger Moth design is its differential aileron control setup. The ailerons (on the lower wing only) on a Tiger Moth are operated by an externally mounted circular bellcrank, which lies flush with the lower wing's fabric undersurface covering. This circular bellcrank is rotated by metal cables and chains from the cockpit's control columns, and has the externally mounted aileron pushrod attached at a point 45º outboard and forward of the bellcrank's centre, when the ailerons are both at their neutral position. This results in an aileron control system operating, with barely any travel down at all on the wing on the outside of the turn, while the aileron on the inside travels a large amount upwards to counter-act adverse yaw.
From the outset, the Tiger Moth proved to be an ideal trainer, simple and cheap to own and maintain, although control movements required a positive and sure hand as there was a slowness to control inputs. Some instructors preferred these flight characteristics because of the effect of "weeding" out the inept student pilot.
Operational history
The RAF ordered 35 dual-control Tiger Moth Is which had the company designation DH 82. A subsequent order was placed for 50 aircraft powered by the de Havilland Gipsy Major I engine (130 hp) which was the DH 82A or to the RAF Tiger Moth II. The Tiger Moth entered service at the RAF Central Flying School in February 1932. By the start of the Second World War, the RAF had 500 of the aircraft in service and large numbers of civilian Tiger Moths were impressed to meet the demand for trainers.
During a British production run of over 7,000 Tiger Moths, a total of 4,005 Tiger Moth IIs were built during the war specifically for the RAF, nearly half being built by the Morris Motor Company at Cowley, Oxford.
The Tiger Moth became the foremost primary trainer throughout the Commonwealth and elsewhere. It was the principal type used in the British Commonwealth Air Training Plan where thousands of military pilots got their first taste of flight in this robust little machine. The RAF found the Tiger Moth's handling ideal for training future fighter pilots. Whilst generally docile and forgiving in the normal flight phases encountered during initial training, when used for aerobatic and formation training the Tiger Moth required definite skill and concentration to perform well — a botched manoeuvre could easily cause the aircraft to stall or spin.
A number of modified Tiger Moths were developed for special roles. A radio-controlled target tug version of the Tiger Moth II called the DH.82B Queen Bee was first built in 1935, with nearly 300 in service at the start of the Second World, (it is believed the name "Drone" derived from "Queen Bee"). These aircraft retained a normal front cockpit for test-flying or ferry flights, but had a radio-control system in the rear cockpit that operated the controls using pneumaticically-driven servos. Four-hundred were built by de Havilland at Hatfield, and a further 70 by Scottish Aviation.
In the aftermath of Britain's disastrous campaign in France, in August 1940, three proposals involved beach defence systems; 350 Tiger Moths were fitted with bomb racks to serve as light bombers as a part of Operation Banquet. A more radical conversion involved the "paraslasher," a scythe-like blade fitted to a Tiger Moth and intended to cut parachutists' canopies as they descended to earth. Flight tests proved the idea, but it was not officially adopted. The Tiger Moth was also tested as a "human crop sprayer" intended to dispense Paris Green poisonous insecticide from powder dispensers located under the wings.
In Canada, de Havilland manufactured 1,523 of the DH 82C, which had a 145 hp D.H. Gipsy Major 1C engine and other modifications including a tail wheel replacing the original tail skid, a stronger undercarriage with wheels set farther forward and enclosed cockpit with a sliding canopy necessitated by the cold northern climate. The de Havilland Canada operation also supplied 200 Tiger Moths to the USAAF, which designated them the PT-24. A further 151 were built in Norway, Sweden and Portugal while 2,949 Tiger Moths were built by other countries of the British Commonwealth.
Postwar
In postwar use, surplus Tiger Moths were made available for sale to flying clubs and individuals. They proved to be inexpensive to operate and found enthusiastic reception in the civil market, taking on new roles including aerial advertiser, aerial ambulance, aerobatic performer, crop duster and glider tug. They were often compared with the Belgian-designed Stampe SV.4 aerobatic aircraft which had a very similar design layout. Several Tiger Moths were converted during the 1950s to Coupe standard with a sliding canopy over both crew positions.
After the invention of aerial topdressing in New Zealand, large numbers of ex-Royal New Zealand Air Force Tiger Moths built in that country and in the United Kingdom were converted into agricultural aircraft. The front seat was replaced with a hopper to hold superphosphate for aerial topdressing. From the mid 1950s, these topdressers were replaced by more modern types such as the PAC Fletcher, and a large number of New Zealand Tiger Moths in good flying condition then passed to enthusiasts.
Royal Navy Tiger Moths utilised as target tugs and "air experience" machines became the last military aircraft when the service purchased a batch of refurbished examples in 1956. One was the last Bi-plane to land on an Aircraft Carrier (HMS Eagle) in English Channel during the Summer of 1967. On take off the wind over the deck meant she took off but was slower than the carrier who turned hard starboard to avoid a possible collision. These remained in service until the early 1970s.
Tiger Moths were often modified to stand in for rarer aircraft in films. Notably, Tiger Moth biplanes were used in the crash scenes in The Great Waldo Pepper, standing in for the Curtiss JN-1.
Flying the Tiger Moth
The Tiger Moth responds well to control input, and is fairly easy to fly for a tail dragger. Its big "parachute" wings are very forgiving, and it stall as slow as 25 knots with power. Its stall and spin characteristics are benign. It has some adverse yaw, and so requires rudder input during turns.
As the Tiger Moth has no electrical system, it must be started by hand. This needs to be done with care to prevent being struck by the propeller which would result in serious injury. Being a tail dragging bi-plane, taxiing also requires care. The pilot cannot see directly ahead, the lower wing can hit obstructions, and it is susceptible to gusts of wind on its inclined, large, upper wing.
The take off is then uneventful, and it has a reasonable rate of climb. However, full power should not be maintained for more than a minute or so to avoid damaging the engine.
The Tiger Moth's biplane design makes it strong, and it is fully aerobatic. But surprisingly it only has ailerons on its bottom wing, which makes its rate of roll relatively slow for a biplane. Most manouvers are started at about 90 to 110 knots, and it has a VNE of 140 knots. It is important to lock the automatic slots (leading edge flaps) during aerobatic manouvers.
"Wheel" landings are straight forward, as the plane is pushed on to the runway at a moderate speed with just the front wheels on the ground, and then the tail is held up until the speed reduces. Being an open cockpit the pilot can stick their head over the side to see the runway. Being a tail dragger it is essential to land it straight with no sideways movement to avoid ground loops.
Three point landings are difficult because there is insufficient elevator authority to pull the tail down into a proper three point position. Instead, the aircraft must be flaired several metres above the ground, then allowed to drop before sharply bring the stick back. If done correctly the resultant angular momentum will bring the tail down far enough to land on all three points.
Variants
- DH.60T Moth Trainer/Tiger Moth
Military training version of the De Havilland DH.60 Moth. First eight prototype DH.82 configuration aircraft were named Tiger Moth.
- DH.82 Tiger Moth (Tiger Moth I)
Two-seat primary trainer aircraft. Powered by a 120 hp (89 kW) de Havilland Gipsy III piston engine; renamed Tiger Moth I in RAF.
- DH.82A Tiger Moth (Tiger Moth II)
Two-seat primary trainer aircraft. Powered by a 130 hp (97 kW) de Havilland Gipsy Major piston engine. Named Tiger Moth II in RAF.
- DH.82B Queen Bee
Unmanned radio-controlled target drone; 380 built. As of 2008, the sole remaining airworthy Queen Bee resides at RAF Henlow, England.
- DH.82C Tiger Moth
Cold weather operations version for the RCAF. Fitted with sliding glass canopies and cockpit heating. Powered by a 145 hp (108 kW) de Havilland Gipsy Major piston engine; 1,523 built.
- PT-24 Moth
United States military designation for the DH.82C ordered for Lend-Lease to the Royal Canadian Air Force; 200 built by de Havilland Canada.
- Thruxton Jackaroo
Four-seat cabin biplane, modified from existing DH.82A airframes.
Military Operators
- Australia
Royal Australian Air Force
Royal Australian Navy - Fleet Air Arm (RAN).
- Belgium
Belgian Air Force (31 operated from 1945)
- Brazil
Brazilian Air Force, 5 delivered in 1932 and 12 in 1935.
- Burma
- Canada
Royal Canadian Air Force
- Ceylon
Royal Ceylon Air Force
- Denmark
- Egypt
- Finland
Finnish Air Force
- France
- Germany
Luftwaffe (small numbers)
- Greece
Hellenic Air Force
- India
Royal Indian Air Force
Indian Air Force
- Iran
Imperial Iranian Air Force
- Iraq
- Israel
Israeli Air Force
Sherut Avir
- Jordan
Royal Jordanian Air Force
- Malaya
Malaya Auxiliary Air Force
- Netherlands
Royal Netherlands Air Force
Dutch Naval Aviation Service
Royal Netherlands East Indies Army Air Force
- New Zealand
Royal New Zealand Air Force
No. 1 Squadron RNZAF
No. 2 Squadron RNZAF
No. 3 Squadron RNZAF
No. 4 Squadron RNZAF
No. 42 Squadron RNZAF
- Norway
Norwegian Army Air Service
- Pakistan
Pakistan Air Force
- Poland
Polish Air Force
Polish Air Force in Great Britain
- Portugal
Portuguese Army Aviation
Portuguese Naval Aviation
Portuguese Air Force
- Rhodesia
Rhodesian Air Force
- Spain
Spanish Republican Air Force
Spanish State
Spanish Air Force
- South Africa
South African Air Force
- Southern Rhodesia
Southern Rhodesian Air Force
- Sri Lanka
Sri Lankan Air Force
- Sweden
Swedish Air Force
- Thailand
- United Kingdom
Royal Air Force
No. 24 Squadron RAF
No. 27 Squadron RAF
No. 52 Squadron RAF
No. 81 Squadron RAF
No. 116 Squadron RAF
No. 297 Squadron RAF
No. 510 Squadron RAF
No. 612 Squadron RAF
No. 613 Squadron RAF
No. 652 Squadron RAF
No. 653 Squadron RAF
No. 654 Squadron RAF
No. 656 Squadron RAF
No. 663 Squadron RAF
No. 668 Squadron RAF
No. 669 Squadron RAF
No. 670 Squadron RAF
No. 671 Squadron RAF
No. 672 Squadron RAF
No. 673 Squadron RAF
Fleet Air Arm
- United States
United States Army Air Force
- Uruguay
Uruguayan Air Force
- Yugoslavia
SFR Yugoslav Air Force
2nd Training Aviation Regiment (1945–1948)
Survivors
Numerous examples of the Tiger Moth are still flying today (an estimated 250). The number of airworthy Tiger Moths has increased as previously neglected aircraft (or those previously only used for static display in museums) have been restored. A number of aircraft have been preserved as museum displays (amongst others) at the:
- Vliegend Museum Seppe in The Netherlands;
- National Museum of Flight in Scotland;
- Mosquito Aircraft Museum in England;
- Malta Aviation Museum in Malta;
- Polish Aviation Museum at the former Kraków-Rakowice-Czyżyny Airport in Poland;
- Museo Nacional Aeronáutico y del Espacio de Chile in Chile;
- Museo Aeronáutico del Uruguay in Uruguay;
- Museu Aeroespacial- (Musal) in Brazil
- Museum of New Zealand Te Papa Tongarewa;
- Alberta Aviation Museum
- Western Canada Aviation Museum in Winnipeg, Manitoba, Canada;
- Shuttleworth Collection at Old Warden, England
- Canadian Museum of Flight
- Sri Lanka Air Force Museum, Sri Lanka
- Yugoslav Aeronautical Museum, Serbia.
- Pakistan Airforce Museum, Karachi, Pakistan
- Israeli Air Force Museum, Hatzerim, Israel
- Mackay Tiger Moth Museum, Mackay, Australia
- RAAF Museum, RAAF Williams Point Cook, Australia
- Temora Aviation Museum, Temora, Australia
- Royal Aero Club of Western Australia, Jandakot, Australia
- Museu do Ar, Portuguese Air Force, Portugal
- Canadian Air & Space Museum - Toronto (www.casmuseum.org)
Specifications (DH 82A)
General characteristics
Crew: 2, student & instructor
Length: 23 ft 11 in (7.34 m)
Wingspan: 29 ft 4 in (8.94 m)
Height: 8 ft 9 in (2.68 m)
Wing area: 239 ft² (22.2 m²)
Empty weight: 1,115 lb (506 kg)
Loaded weight: 1,825 lb (828 kg)
Powerplant: 1× de Havilland Gipsy Major I inverted 4-cylinder inline, 130 hp (100 kW)
Performance
Maximum speed: 109 mph at 1,000 ft (175 km/h at 300 m)
Range: 302 miles (486 km)
Service ceiling: 13,600 ft (4,145 m)
Rate of climb: 673 ft/min (205 m/min) |