The Scottish Aviation Twin Pioneer was a British STOL transport aircraft built by Scottish Aviation Limited at Prestwick Airport, Scotland, during the 1950s. It was designed for both civil and military operators. It was conceived as a twin-engined version of the Pioneer light transport. Both aircraft required "an area only 30m (99ft) by 275m (902ft) in which to operate."[2]
Early in its operational life in 1957 the Twin Pioneer suffered two fatal accidents due to fatigue failure which caused the outer panel of the wing to detach from the aircraft in flight.[8][9] This issue required significant re-design of the structure and adversely impacted sales.[10]
Operational history
Scottish Aviation Twin Pioneer at LabuanRAF Twin Pioneer CC.1 wearing sand camouflage in service in 1968.
The military version could carry external stores such as bombs under the stub wings. One aircraft became the first aircraft for the newly formed Royal Malaysian Air Force when it was delivered on 16 January 1962; the type served with the air force for 12 years.
The Royal Air Force ordered 39 aircraft, which were built between 1958 and 1959, deployed in Aden and the Far East.[10] It was used extensively by British forces in the Malayan Emergency and the later confrontation in Borneo. In August 1959, No. 78 Squadron RAF at Khormaksar received some Twin Pioneers to supplement its single engine Pioneers.[11] The Twin Pioneers were employed in moving troops and supplies around the wilderness and on occasions lending support to the Sultan of Oman. A series of double engine failures caused problems with the squadron losing two aircraft on the same day. Unsuitable soft and hard landing strips were also causes of failures during landings.
Other squadrons that operated the Twin Pioneers were No. 152 Squadron RAF based at Muharraq in Bahrain and No. 21 Squadron RAF,[11] which reformed with the type at Benson in May 1959. The squadron then moved to Kenya and in June 1965 to Aden. No. 152 operated around the Persian Gulf and in 1959, No. 209 Squadron RAF based at Seletar began to receive Twin Pioneers. These operated in Borneo and Malaya. The SRCU (Short Range Conversion Unit) at RAF Odiham also flew three Twin Pioneers for aircrew training. RAF No. 230 Squadron in the UK was the last military operator of the Twin Pioneer. The squadron operated the type in an interesting sand-colour camouflage scheme.
Although mainly used in military operations, the Twin Pioneer was also successful as a commercial transport for operation in areas without proper airfields, where unprepared surfaces were often the norm. Twin Pioneers were sold as survey aircraft to oil exploration companies with some of the first sales to Rio Tinto Finance and Exploration Limited, and the Austrian and Swiss government survey departments. Three were used by the 'Kroonduif' in Dutch New Guinea.
Twin Pioneer Mk 3 G-AZHJ has been acquired by the South Wales Aviation Museum at St Athan for restoration as a museum exhibit.[20]
Twin Pioneer Mk 2 G-APRS (G-BCWF) was airworthy in the collection of the Classic Air Force, Coventry, England.[21] It was transported to Stirling, Scotland in July 2018 to be converted to a 'glamping' home.[22]
Incidents and accidents
Structural failure caused the first Twin Pioneer crash, of JZ-PPX operated by Kroonduif of Indonesia on 30 Aug 1957 about 8 miles off Japen Island, Papua New Guinea, both occupants died.[8]
The same structural failure also caused the second Twin Pioneer crash, of G-AOEO operated by Scottish Airlines on 7 Dec 1957 near Fezzan, Libya, all 6 on board died, including David McKintyre, the co-founder of Scottish Aviation Limited and a driving force behind the company.[9][10]
On 10 March 1960, G-ANTP, operated by Scottish Airlines, crashed on take-off at Jorhat-Rowriah Airport, India, killing all 3 persons on board.[23]
A recorded loss of a Twin Pioneer occurred on takeoff from Limbang Airport on 17 May 1967. The aircraft, operated by Malaysia-Singapore Airlines, carried the registration 9M-ANC. The cause was given as unknown.[24]
In Royal Air Force service three aircraft had fatal accidents:
2 March 1961 – XL966 of 21 Squadron flew into rising ground at Mount Meru, Tanganyika, Tanzania, one killed.
14 February 1963 – XN318 of 209 Squadron flew into a wooded cliff in Borneo, all five onboard killed.
18 April 1963 – XL994 of 152 Squadron dived into the ground near Bu Hafafa in Oman, all eight onboard killed.
On 14 May 1963, the Scottish Aviation Twin Pioneer 3, PK-GTCGaruda Indonesian Airways, damaged beyond repair. No one injuries.[25]
On 20 September 1963, a Scottish Aviation Twin Pioneer 1, registration PK-GTBGaruda Indonesian Airways, crashed into terrain. Other reports say this Twin Pioneer was damaged on landing. Killed all 7 people on board.[26]
Fuel capacity: 371 imp gal (446 US gal; 1,687 L) in military versions + 1 or 2 100 imp gal (120 US gal; 455 L) cabin auxiliary tanks; (247 imp gal (297 US gal; 1,123 L) in civil versions); 9 imp gal (11 US gal; 41 L) oil tank in each engine nacelle
Powerplant: × Alvis Leonides 514/8 9-cylinder air-cooled radial piston engine, 540 hp (400 kW) for take-off
