Eurocopter/Kawasaki BK117A-4
Twin-engine medium utility helicopter, France
Archive Photos 1
Eurocopter/Kawasaki BK117A-4 (N625MB, c/n 7108, 1999) on display (c.1990s) at the Marine Corps Air Station El Toro Airshow, and MCAS El Toro, California (Photos by John Shupek)
Overview 2
- MBB/Kawasaki BK117
- Role: Utility/transport
- National origin: Germany/Japan
- Manufacturer: Messerschmitt-Bölkow-Blohm (MBB)/Kawasaki Heavy Industries
- First flight: 13 June 1979
- Introduction: 9 December 1982
- Status: Production ceased
- Primary users: DRF; ADAC
- Produced: 1979-2004
- Number built: 444
- Developed from: MBB Bo 105
- Developed into: Eurocopter EC 145
The MBB/Kawasaki BK117 is a Twin-engine medium utility-transport helicopter. It was a joint development between Messerschmitt-Bölkow-Blohm (MBB) of Germany and Kawasaki of Japan. MBB was later purchased by Daimler-Benz and eventually became a part of Eurocopter. The BK117 is popular for passenger and VIP-transport, seating from seven up to 10 people. It is also used for aerial crane and sling work, law enforcement, and military transport, and is exceptional as an air ambulance and search and rescue platform. Its successor was developed from the BK117C-1 version. It is produced as the EC 145.
Development 2
The BK117 was a joint development between MBB and Kawasaki based on an agreement made on 25 February 1977. The agreement would replace two separate projects for Twin-engine general purpose helicopters; the Bo 107 by MBB and the KH-7 from Kawasaki. Costs were shared equally, with MBB developing the rotors (based on the rigid rotor system used on MBB’s Bo 105), tailboom, flight controls and hydraulic system and Kawasaki developing the landing gear, airframe, main transmission and other minor components. Each company would have its own assembly line producing aircraft for local markets.
Each company was to build two prototypes (although Kawasaki only built one) to be completed by 1979; one for flight testing and the others for tie down testing and static testing. MBB’s flying prototype made its first flight at Ottobrunn on 13 June 1979, followed by the Kawasaki prototype at Gifu on 10 August 1979. Development was slower than expected, a problem made worse by shortages of skilled manpower available at MBB. Although it was originally planned for airworthiness certification to be achieved before the end of 1980, German certification was not achieved until 9 December 1982, with Japanese certification following on 17 December, and the all-important United States FAA certification being obtained on 29 March 1983.
A single BK117A-3 (c/n 7106) was leased by the Canadian Forces Air Command for a test program and designated as the CH-143. When the program was over, the aircraft was returned to MBB Canada.
In total, 444 BK117’s were made; 329 (and two prototypes) by MBB at Donauworth, 111 (and one prototype) by Kawasaki in Japan.
Japanese Production:
- BK117A-1 to C-1: c/n 1001-1112 = 111 + P-3/P-5 Prototype
German Production:
- BK117A-1 to B-2: c/n 7001-7275 = 274
- BK117C-1: c/n 7500-7555 = 56
- + P-2 Prototype + S-01 Pre-production Prototype
- NOTE: The last variant of the BK117 was the C-1. The BK117C-2 is actually the brand name for the EC 145 for the Australasian market, and as such is an EC 145, not a BK117.
Variants 2
- BK117P-2 (D-HBKA): German prototype, first flown 13 June 1979. Now exhibited at the Bückeburg helicopter museum, Bückeburg, Germany.
- BK117P-3/P-5 (JQ0003): Japanese prototype, first flown 10 August 1979. Now exhibited at Kakamigahara Aerospace Museum Kakamigahara/Gifu, Japan.
- BK117S-01 (D-HDRF): Initial pre-production version. Now preserved on top of the DRF-Headquarters at Stuttgart Airport.
- BK117A-1: Powered by two Lycoming LTS 101-650B-1 engines. First flown 23 April 1982.
- BK117A-3: Introduced in March 1985, the A-3 has a larger tail rotor with improved blades, Yaw CSAS, improved stability (SPAS) and the take-off weight increased to 3,200 kg (7,055 lb).
- BK117A-4: Introduced in July 1986, the A-4 has increased transmission limits at take-off power, improved tail rotor head. German aircraft have provision for extra internal fuel, giving enhanced performance.
- BK117A-3M: Military version introduced in 1986. The A-3M is fitted with taller skids and can carry 11 troops. A Browning 12.7 mm (0.5 in) machine gun can be mounted under the fuselage in a Lucas turret with 450 rounds and controlled by a helmet-mounted sight. The A-3M also has outrigger pylons which can hold up to eight HOT II or TOW antitank missiles or a variety of air-to-air missiles, rocket-pods, or forward-firing cannons. Provisions for a doorway gunner’s position with a 12.7 mm (0.5 in) gun can also be installed.
- BK117B-1: Introduced in December 1987, the B-1 is fitted with LTS 101-750B-1 engines to provide increased performance, and a 140 kg (309 lb) increase in payload.
- BK117B-1C: UK-certified version with reduced range and endurance.
- BK117B-2: Maximum Gross Weight increased to 3,350 kgs, 2 × Allied Signal Lycoming LTS101-750B-1 engines fitted as standard, new tail rotor blades, improved hot and high performance, take-off/landing limitation increased to 15,000 ft, improved flight performance for: HIGE/HOGE, single engine service ceiling.
- BK117C-1: Powered by two Turbomeca Arriel 1E engines. Later models may be upgraded to Arriel 1E2 engines.
- NBK117: License-built model produced in Indonesia.
- BK117-850D2: Introduced in 2010, the 850D2 variant is an STC (Supplementary Type Certificate) development (i.e., re-engined) of BK117B-2 incorporating Honeywell LTS 101-850B-2 engines aimed at improving OEI and Category A performance. Development and certification was conducted in New Zealand by Airwork of Ardmore, NZ, in conjunction with Flight Structures Ltd and Honeywell.
Operators 2
Civil Operators
The majority of the helicopters are operated by various emergency services although it is also operated by private individuals, companies and executive charter operators.
- Australia: New South Wales Police Force; New South Wales Fire Brigades; New South Wales Rural Fire Service; Westpac Life Saver Rescue Helicopter Service; Western Australia Police; Energex Rescue Helicopter
- Canada: Shock Trauma Air Rescue Society
- Germany: ADAC; Deutsche Rettungsflugwacht
- Greece: Greek Fire Department
- Kenya: Everett Aviation
- New Zealand: Auckland Rescue Helicopter Trust; Northland Emergency Services Trust; Otago Rescue Helicopter Trust; Lifeflight Trust - Wellington; Hawkes Bay Helicopter Rescue Trust; Helipro Gardencity Helicopters; Westpac Rescue Trust
- Peru: Peruvian National Police
- Puerto Rico: Puerto Rico Police Department; Aeromed Air Ambulance Service
- South Africa: South African Police Service
- Spain: Servicio de Vigilancia Aduanera
- Taiwan: Daily Air Corporation
- United States: Sentara Norfolk General Regional Air Ambulance, in operation since 1996; Mercy Flight Central, Inc. of Canadaguia, NY.; Air Methods; Omniflight
Military Operators
- Chile: Carabineros de Chile
- Spain: Guardia Civil
- South Africa: South African Air Force
Former Military Operators
- Bophuthatswana: Bophuthatswana Air Force
- Canada: Canadian Forces Air Command - A single BK117-A3 was leased by the CF for a test program and designated as the CH-143. When the program was over, the aircraft was returned to MBB Canada.
- Chile: Chilean Air Force
- Ciskei: Ciskei Defence Force
- Colombia: Colombian National Armada
- Germany: Luftwaffe - Former operator, one helicopter.
- Iraq: Iraqi Air Force
- Japan: Technical Research and Development Institute
- Jordan: Royal Jordanian Air Force - One aircraft.
- Lesotho: Lesotho Defence Force
- Transkei: Transkei Defence Force
- Venda: Venda Defence Force
Specifications (BK117B-2) 2
General Characteristics
- Crew: 1
- Capacity: up to 10 passengers
- Length: 9.91 m (32 ft 6 in) (fuselage length)
- Height: 3.85 m (12 ft 8 in) (rotors turning)
- Empty weight: 1,727 kg (3,807 lb)
- Max takeoff weight: 3,350 kg (7,385 lb)
- Fuel capacity: 697 L (183 US Gallons, 153 Imp Gallons) internal fuel
- Powerplant: 2 × Textron Lycoming LTS 101-750B-1 turboshaft, 442 kW (593 hp) each
- Main rotor diameter: 11.00 m (36 ft 1 in)
- Main rotor area: 95.03 m² (1,022.9 ft²)
Performance
- Maximum speed: 250 km/h (155 mph; 135 kn) at sea level
- Never exceed speed: 278 km/h (173 mph; 150 kn)
- Range: 541 km (336 mi; 292 nm)
- Service ceiling: 4,575 m (15,010 ft) (max certified altitude)
- Hover Ceiling: 3,565 m (11,700 ft) (in ground effect)
- Rate of climb: 11.00 m/s (2,165 ft/min)
References
- Shupek, John. Photos, copyright © 2000 Skytamer Images. All Rights Reserved
- Wikipedia, the free encyclopedia, MBB/Kawasaki BK117