Country of origin:

United Kingdom

Description:

General-purpose utility helicopter

Power Plant:

One 388 kw (520 hp) Alvis Leonides Mk 73 seven-cylinder air-cooled radial engine

Specifications:

History:

The first prototype of the Bristol 171 Sycamore, a Mk 1 (serial VL958), was flown on 27 July 1947, with the second, a Mk 2 (VL963), being flown in February 1948. The type subsequently entered production in various models for the British armed services, and small numbers were sold overseas. The first prototype was fitted with the 336 kw (450 hp) Pratt & Whitney Wasp Junior radial engine and the sole Mk 2 had a 410 kw (550 hp) Alvis Leonides engine. The first production model, the Mk 3, had five seats in lieu of four, a shortened nose to improve downward view, and a wider fuselage. Fifteen were produced (c/ns 12886 to 12900).

The first military production model was the Sycamore HC-10, which was used as an aerial ambulance by the British Army. The HC-11 was then released for communications and observation duties, followed by the HR-12 search-and-rescue variant for RAF Coastal Command, the HR-13 for search-and-rescue for RAF Fighter Command, and the HR-14, which had a lengthened nose, and was used for search, rescue and communications by the RAF.

In the 1950s eleven Sycamore HR-50s and HR-51s, which were export variants of the HR-13 and HR-14, were supplied to the Royal Australian Navy (RAN). The first three were HR-50s (serials XA219, XA220, XA221 – c/ns 13063 to 13065) with a taller and stronger undercarriage for shipboard operations which were completed by December 1952 and carried out deck-landing trials on board ‘HMS Triumph’ in January 1963, and on 16 January were flown on board ‘HMAS Vengeance’.

Further machines were obtained, these being the HR-51 variant, equivalent to the HR-14, the pilot’s position being changed from left to right hand to conform to American helicopter practice, these becoming XD653 (c/n 13146 – ex G-AMWJ), XD654 (c/n 13147), XD655 (c/n 13147) and XD656 (c/n 13148). In March 1956 a further two HR-51s were obtained for the aircraft carrier ‘HMAS Melbourne’, becoming XK902 (c/n 13401) and XK903 (c/n 13407), but the latter was later re-serialled XL507. On 25 October 1956 No 723 Squadron RAN was disbanded and all aircraft were transferred to No 724 Squadron.

Further machines were delivered to the RAN by merchant ship in 1958. XN448 (c/n 13270 – ex G-18-5, CF-HVX, G-AOBM), the first of these having previously been used as a demonstrator in Canada, was later refurbished for the RAN. In 1959 XN449 (c/n 13504 – ex G-18-177) and XN450 (c/n 13505 – ex G-18-178) were delivered. A Sycamore was normally embarked on board ‘HMAS Melbourne’ for search-and-rescue duties up until 1964. During 1960-1961 Army pilots were trained on the Sycamore at ‘HMAS Albatross’, Nowra, NSW pending delivery of the Bell 47G to that service. Deliveries to Australia took place between March 1953 and August 1961.

The type saw service with Nos 723 and 724 Squadrons, a number being lost whilst in service with the RAN. The fates of these aircraft were: XA219 became an instructional airframe at ‘HMAS Nirimba’ at Schofields, NSW; XA220 was sold to Business Aviation and taken to Camden, NSW, later being transferred to the Sydney Technical College at its Bankstown, NSW hangar for some years for apprentice training but later went to the RAN Museum at ‘HMAS Albatross’; XD653 (c/n 13071) also went to the RAN Museum at Nowra; XA221 crashed during flood rescue operations on 25 February 1955 near Singleton Station, NSW and was reduced to spares; XD654 (c/n 13145) eventually was lost when it crashed into the sea near the Cocos Islands on 4 March 1961.

XD655 (c/n 13417) crashed near St Georges Basin, NSW on 12 October 1955; XD656 (c/n 13147) ditched off ‘HMAS Melbourne’ on 11 November 1957; XK902 (c/n 13401) crashed at Bald Knob Range, NSW on 10 January 1958 whilst supporting survey operations with ‘HMAS Warrego’ when the ship was charting coastal waters; XL507 (c/n 13407) ditched off ‘HMAS Melbourne’ on 24 May 1957; XN449 (c/n 13504) crashed at Nowra on 3 September 1982, when the engine failed, and was destroyed; XN450 (c/n 13505) was sold to Business Aviation Ltd, later going to Associated Helicopter Services Pty Ltd. It later went to the Camden Aviation Museum at Narellan, NSW and was later again transferred to and remains with the Sid Beck collection at Mareeba, QLD.

XR592 (c/n 13070 – ex VH-BAW, G-AMWI) was built as a Mk 4 and was modified to HR-51 standard. It was at one stage marked incorrectly as XN635 but this serial had been allotted to an RAF Jet Provost T.3 so it was re-numbered. It survives preserved with the Camden Museum of Aviation. XN448 was sold and became VH-SYC on 14 February 1967 but was damaged landing on 2 November 1968 near Wyndham, WA. The wreck was abandoned. Attempts to recover it for a museum were unsuccessful.

One of the RAN machines was used during rescue work related to the loss of the ‘HMAS Voyager’ off the NSW south coast. VH-GVR (ex A91-1 – c/n 12894), VH-SYC (c/n 13270 – ex XN448) and VH-BAW (c/n 13070 – ex XR592) were all at one stage owned by J Rose Motors, a Victorian company, the latter two being ex-RAN machines.

Two Sycamores were also supplied to the RAAF, the first becoming A80-2 (A80-1 being a Sikorsky S-51), but this serial was later changed to A91-1 (c/n 12894 – ex G-ALSZ, WV695). This machine was flown to Australia on board Bristol Freighter A81-4 and was operated by the RAAF Air Trials Unit. The second Sycamore became A91-2, eventually being damaged in a forced landing near Lake Heart, SA on 13 December 1960. These aircraft were used at Woomera for some time. A91-1 was sold in 1965 and became VH-GVR. It crashed at Falls Creek, VIC, on 25 January 1967 in the Victorian Alps. The wreck was taken to Albury and was later acquired by the Moorabbin Aircraft Museum for restoration and display. A91-2 was scrapped in July 1961. A91-2 was a Mk 4 with an up-rated engine, whereas A9-1 was a Mk 3.

Five Sycamores have appeared on the Australian Civil Aircraft Register over the years. VH-INQ (Mk 3A – c/n 13068) and VH-INO (Mk 4 – c/n 13403 – ex G-AODL – ‘Yarrana’) both served with Ansett/ANA. VH-INO was an ex-British European Airways machine registered to Australian National Airways on 1 May 1956 and immediately entered service in Tasmania with the Hydro Electric Authority. At one stage it was fitted out for spraying operations but crashed in the Nundle State Forest, NSW on 11 January 1960. VH-INQ was lost in an accident at Glengyle, QLD on 4 September 1961.

In 1968 Associated Helicopters, a subsidiary of Nesbo Aviation, obtained four ex-RAN Sycamores, these aircraft being overhauled and rebuilt for civilian use, the first becoming VH-BAW. This machine had previously been commissioned in 1953 as a demonstration aircraft, being shown at the 1953 Farnborough Air Show and later making a tour of Switzerland. It was later used to test rotor blades and suffered a number of forced landings during this time. It was imported, as noted above, for the RAN in 1961 and was used for general reconnaissance, search- and-rescue, and ambulance work. It was used for demonstration flights in Sydney, NSW and carried out a four month exploration program in central Australia.

Of the 178 Sycamores built, 69 were exported, the biggest operator being West Germany, which put 50 examples into service, mainly with the Luftwaffe but a number to the Germany Navy. One example was still airworthy in 2017. This ex-German aircraft (c/n 13475) was built at Weston-super-Mare in Somerset with the registration G-18-148 and saw service with the Luftwaffe as a VIP transport at Cologne with the serial CA+328. It later entered civil service as D-HALD in 1972 and joined a fleet of the type with Hubschrauber-Flugdienst. It was sold in 1988 as HB-RXB to an operator in Altenrhein, Switzerland. It later joined the Red Bull group ‘The Flying Bulls’ in Austria and has been painted as an RAF Air Support Command machine with the serial XG545, attending aviation events in Europe.