The Britten-Norman BN-2 Islander

The Britten-Norman BN-2 Islander is a 1960s British light utility aircraft, mainline airliner and cargo aircraft designed and originally manufactured by Britten-Norman of the United Kingdom. The Islander is one of the best-selling commercial aircraft types produced in Europe. Although designed in the 1960s, over 750 are still in service with commercial operators around the world. The aircraft is also used by the Army and Police forces in the United Kingdom and is a light transport with over 30 military aviation operators around the world.

Design and development

Britten-Norman was started in 1953 to convert and operate agricultural aircraft. It also produced hovercraft (Cushioncraft, later sold to the British Hovercraft Corporation). Design of the Islander started in 1963 and the first prototype BN-2 first flew on 13 June 1965, with the second prototype on 20 August 1966. Both of these aircraft had engines that were less powerful than the production versions. The Islander is a high-wing cantilever monoplane with a rectangular fuselage and two wing-mounted engines. A conventional tail unit and a fixed tricycle landing gear, the fuselage will usually accommodate one pilot and up to nine passengers.

The production Islander first flew on 24 April 1967 and was certified in August 1967. Production started at the Britten Norman factory at Bembridge, Isle of Wight but within a few years the company could not keep up with demand, a contract was placed with IRMA of Romania initial to produce aircraft from a kit of parts but the Romanian factory soon became the main source for production Islanders. A military version of the Islander, first flown in 1970, was marketed as the Defender with underwing hard points and fitted out as a light troop transport and support aircraft.

The second prototype was developed into a stretched Super Islander but the program was stopped and the aircraft was used as a basis of the three-engined version, the Trislander. The company had financial difficulties and by the end of 1970 went into receivership. In 1972 the company was bought by the Fairey Aviation Group and production of the Islander and Trislander was moved to their factory (Avions Fairey) in Gosselies in Belgium although the aircraft were flown to Bembridge for final customer preparation. The new company developed the Turbo Islander with Lycoming LTP101 turboprops but the engines were too powerful for the aircraft and the design evolved into the Turbine Islander (BN-2T) with Allison 250 turboprops. Fairey then suffered financial problems and called in the receiver and the Fairey Britten Norman company was sold to Pilatus of Switzerland.

An improved version, the BN-2A Islander, first flew in 1969. It incorporated aerodynamic and flight equipment improvements as well as changes to the baggage arrangements.

In 1978 a further improved version, the BN-2B Islander II was introduced. Improvements included increased carrying capacity and propeller modifications to reduce noise levels. Options included a long-nosed version for increased baggage capacity, raked wingtip auxiliary fuel tanks and twin Allison 250-B17C turboprop engines. When the latter are installed the aircraft is designated the BN-2T Turbine Islander.

The Defender 4000 is a military conversion of the Islander, capitalizing on its rugged structure for use in Third World countries. Purchases from police and military customers centres around use in surveillance and counter-terrorism operations. The Maritime Defender is another military version of the Islander, intended for search and rescue, coastal patrol and fishery protection.
Licensed production

Companies in addition to Britten-Norman have manufactured the Islander. IRMA from Romania has been building the aircraft since 1969, including the SONACA (Fairey), in Gosselies, Belgium. 35 have also been assembled by the National Aero Manufacturing Corporation in the Philippines.

Britten-Norman Trislander

A design project to develop an Islander with a larger capacity resulted in the BN-2A Mk III Trislander. This aircraft has a stretched fuselage, modified landing gear and a third (tail-mounted) engine. The prototype was constructed from the original second BN-2 prototype and flew on 11 September 1970.

Variants

BN-2: Prototype first flown in 1966 with two 260 hp Lycoming O-540-E4B5 piston engines.
BN-2A: Production version with minor modification from prototype and increased Takeoff weight.
BN-2A-2: A BN-2A with modified flaps, and two 300 hp Lycoming IO-540-K1B5 (fuel injected) engines.
BN-2A-3: A BN-2A-2 with increased wingspan and fitted with extra wingtip fuel tanks.
BN-2A-6: A BN-2A with wing leading edge modifications and two 260 hp Lycoming O-540-E4C5 engine.
BN-2A-7: A BN-2A-6 with increased wingspan and fuel capacity.
BN-2A-8: A BN-2A-6 with droop flaps.
BN-2A-9: A BN-2A-7 with droop flaps.
BN-2A-10: A BN-2A-8 with increased takeoff weight and 270 hp Lycoming TIO-540-H1A (turbo-charged, fuel injected) engines.
BN-2A-20: A BN-2A-2 with increased takeoff weight and minor improvements.
BN-2A-21: A BN-2A-3 with increased takeoff weight.
BN-2A-23: A BN-2A-21 with lengthened nose.
BN-2A-24: A BN-2A-26 with lengthened nose.
BN-2A-25: A BN-2A-27 with lengthened nose.
BN-2A-26: A BN-2A-8 with increased takeoff weight.
BN-2A-27: A BN-2A-9 with increased takeoff weight.
BN-2A-41: Turbo Islander with lengthened nose, droop flaps and two Lycoming LTP-101 turboprops, first flown in 1977.

Britten-Norman BN-2B Defender

Defender military variant with 300 hp IO-540-K1B5 engines and underwing hard points and military modifications.

BN-2B-20: A BN-2A-20 with improved soundproofing and increased landing weight and other minor modifications.
BN-2B-21: A BN-2A-21 with Model B improvements.
BN-2B-26: A BN-2A-26 with Model B improvements.
BN-2B-27: A BN-2A-27 with Model B improvements.
BN-2T: Turbine Islander based on BN-2A-26 with two 320 shp Allison 250-B17C turboprops.

Islander AL.Mk 1

Twin-engined communications, reconnaissance aircraft for the British Army; seven built.

Islander CC.Mk 2 and CC.Mk 2A

Twin-engined communications aircraft for the RAF; three operated.

Maritime-Defender

Armed maritime reconnaissance and patrol aircraft.

BN-2A-III Trislander

Three engined Trislander, a stretched BN-2A with 18 seats and three 260 hp Lycoming O-540-E4C5 piston engines.

Specifications (BN-2A Islander)

General characteristics

* Crew: One or two pilots
* Capacity: Up to nine passengers
* Length: 35 ft 8 in (10.86 m)
* Wingspan: 49 ft (14.94 m)
* Height: 13 ft 9 in (4.18 m)
* Wing area: 325 ft² (30.2 m²)
* Empty weight: 3,675 lb (1,667 kg)
* Loaded weight: Up to 6,600 lb (BN2A-20 onwards) (2,994 kg)
* Max takeoff weight: 6,600 lb (2,994 kg)
* Powerplant: 2× Lycoming O-540-E4C5 or IO-540, 260 hp or 300 hp if fuel injected (195 kW) each

Performance

* Maximum speed: 170 mph (273 km/h)
* Cruise speed: 160 mph (257 km/h)
* Stall speed: 40 mph (64 km/h)
* Minimum controllable speed: 45 mph (72 km/h)
* Range: 874 miles (1,400 km)
* Service ceiling: 13,200 ft (4,024 m)
* Rate of climb: 970 ft/min (295 m/min)
* Wing loading: 20 lb/ft² (9.78 kg/m²)

Related development

* Britten-Norman Trislander
* Britten-Norman Defender

Comparable aircraft

* Dornier Do 28