MBB Bo 105

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Bo 105
Bölkow Bo 105 (aka).jpg
A German-registered Bo 105
Role Light utility helicopter
Manufacturer Messerschmitt-Bölkow-Blohm (MBB)
First flight 16 February 1967
Introduction 1970
Status In service
Primary users German Army
Indonesian Army
Spanish Army
Philippine Navy
Produced 1967[1]-2001
Number built 1,500+[1]
Unit cost
$354,700 (1975)[2]
$1.86 million (1991)[3]
Developed into MBB/Kawasaki BK 117
Eurocopter EC 135

The Messerschmitt-Bölkow-Blohm Bo 105 is a light, twin-engine, multi-purpose helicopter developed by Bölkow of Ottobrunn, Germany. It holds the distinction of being the first light twin-engine helicopter in the world, and is the first rotorcraft that could perform aerobatic maneuvers, such as inverted loops.[4][5] The Bo 105 features a revolutionary hingeless rotor system, at that time a pioneering innovation in helicopters when it was introduced into service in 1970. Production of the Bo 105 began at the then-recently merged Messerschmitt-Bölkow-Blohm (MBB).

The main production facilities for producing the Bo 105 were located in Germany and Canada; due to the level of export sales encountered, additional manufacturing lines were set up in Spain, Indonesia, and the Philippines.[6] MBB became a part of Eurocopter in 1991, who continued production of the type until 2001. The Bo 105 was formally replaced in Eurocopter's product range by the newer Eurocopter EC 135, which was itself a development of the Bo 105.

Development

In 1964, development work began at Bölkow upon the helicopter that would become the Bo 105, although work on the hingeless rotor it would use had begun earlier.[7] On 16 February 1967, the second Bo 105A prototype conducted its maiden flight at Ottobrunn in Germany; the first public demonstration was held in May 1967.[1] The test program was broken down into stages as the Bo 105 comprised a new airframe, new rotor system, and a new engine; thus the flying Bo 105 prototype was initially equipped with a main rotor from Westland Helicopter's Scout rotorcraft and a pair of Allison Model 250 turboshaft engines instead of their production counterparts.[7] Sud Aviation worked with Bölkow on developing the rotorcraft; an Alouette II helicopter was modified with the Bo 105's rotor and used to test its performance envelope. The third Bo 105 prototype was equipped with the initial production standard MAN Turbo 6022 turboshaft engines; a total of six pre-production Bo 105s were constructed for testing.[7]

Offshore-configured Bo 105

On 13 October 1970, the German Civil Aviation Authority certified the B0 105; initial deliveries for the first customers, ADAC Air Rescue and the Bavarian State Police, took place shortly thereafter. In 1972, further type certification was granted by the Federal Aviation Administration (FAA) and the Civil Aviation Authority (CAA), enabling export orders from the United States and Britain respectively, which soon followed.[8] In 1972, an improved version of the rotorcraft with more powerful engines, the Bo 105C, was developed, this model quickly superseded the Bo 105A.[8] In 25 September 1973, the prototype Bo 106 performed its first flight;[9] the Bo 106 shared many similaries to the Bo 105, the principle difference being a widened cabin area, capable of seating three abreast in the front row and four abreast in the rear of the cabin. However, nothing further came of the Bo 106 project.[10]

In 1976, the Bo 105CB, equipped with more powerful Allison 250-C20B engines, was introduced. The Bo 105C was further developed to become the Bo 105CBS, the primary change of which being a fuselage stretch of 10 inches to meet the demands of the American for emergency medical service (EMS) operations; this version was often referred to as the Bo 105 Twin Jet in the United States. US aerospace firm Boeing-Vertol served as a partner in the type's production and further development, and marketed the BO 105 in the US market.[2][11] The Bo 105 CB and the Bo 105 CBS variants were also subject to license manufacturing agreements, leading to them being produced by the Philippine Aerospace Development Corporation in the Philippines, Indonesian Aerospace (IPTN) in Indonesia, and Construcciones Aeronáuticas SA (CASA) in Spain in addition to the main production line in Germany.[8][12]

In 1984, the Bo 105LS was developed with the enlarged fuselage of the Bo 105CBS combined with more powerful Allison 250-C28C engines to increase the maximum take-off weight as well as hot-and-high flight performance; the Bo 105 LS was manufactured under a cooperative arrangement with Eurocopter Canada.[8] Improvements and modifications to the Bo 105 LS continued until 1995.[8]

Production of the Bo 105 by Eurocopter formally ended in 2001, principally due to the type having been superseded by the more modern Eurocopter EC 135, itself a direct development from the Bo 105. By the end of production, a total of 1,406 rotorcraft had been manufactured and delivered to operators in 55 nations worldwide.[8]

Design

A view of a Bo 105's engine, transmission, and main rotor

The Bo 105 has a reputation for having high levels of maneuverability; certain variants have been designed for aerobatic maneuvers and used for promotional purposes by operators, one such operator in this capacity being professional pilot Chuck Aaron, flying for Red Bull.[13][14] During the 1970s, the Bo 105 was known for having a great useful load capacity and higher cruise speed than the majority of its competitors.[15] While not being considered a visually attractive helicopter by some pilots; the Bo 105 was known for possessing steady, responsive controls and a good flight attitude.[3] Most models could perform steep dives, rolls, loops, turnovers, and various aerobatic maneuvers, according to MBB the B0 105 is cleared for up to 3.5 positive G force and one negative.[16] One benefit of the Bo 105's handling and control style is superior takeoff performance, including significant resistance to catastrophic dynamic rollover;[17] a combination of weight and the twin-engined configuration enables a rapid ascent in a performance takeoff.[18]

Perhaps the most significant feature of the Bo 105 is its rotor blades and rotor head. The rotor system is entirely hingeless, the rotor head consisting of a solid titanium block to which the four blades are bolted;[19] the flexibility of the rotor blades works to absorb movements typically necessitating hinges in most helicopter rotor designs.[16] The rotor blades are made from reinforced-plastic glass-fiber composite material; its flexibility of the main rotor allowed for active elements other than rotor pitch changes to be removed, greatly simplifying maintenance and extending blade lifespan.[20] The reliability of the advanced rotor system is that, in over six million operating hours across the fleet, there had been a total of zero failures.[21] The rigid rotor blade design adopted on the Bo 105 has been partially attributed as responsible for the type's agility and responsiveness, it remained an uncommon feature on competing helicopters throughout the Bo 105's production life.[17]

Military operators would commonly operate the type at a very low altitude to minimise visibility to enemies, the Bo 105 being well matched to such operations as the helicopter's flight qualities effectively removed or greatly minimised several of the hazards such a flight profile could pose to pilots.[22] When outfitted with optional auxiliary fuel tanks, a basic model Bo 105 would have a flight endurance of roughly five hours under load.[18] In the event of a single engine failure, the Bo 105 could typically continue its flight, albeit with a reduction in cruise speed and range.[20] Besides the two pilots, the cabin can be configured to accommodate up to three passengers on a single rear bench, which can be removed to make room for cargo or a stretcher, which can be loaded and unloaded via the large clamshell doors located at the rear of the fuselage.[23] In a maritime context, the BO 105 can be equipped with auxiliary fuel tanks, emergency flotation equipment, an inflatable life raft, folding rotor blades and high skid landing gear.[24]

Operational history

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Germany Army Bo 105, 1986

The Royal Netherlands Air Force ordered a total of 30.[citation needed]

In 1975, the decision to procure a specialist anti-tank version armed with up to six Euromissile HOT missiles, designated as the Bo 105 PAH-1, for the German Army was made. A total of 212 Bo 105 PAH-1s were delivered between 1979 and 1984.[8] German Army leaders saw the PAH-1 as a temporary measure only, having originally sought a more capable anti-tank helicopter; they were particularly dissatisfied with the PAH-1's inability to perform nighttime combat missions and its self-protection capabilities; ultimately, the Eurocopter Tiger was later developed to as a replacement.[25] In 1977, the German Ministry of Defence selected the Bo 105C for its light observation helicopter (VBH) program, leading to the procurement of another 100 rotorcraft.[8]

During the 1970s, MBB issued a license to produce the Bo 105 to Indonesian Aerospace (IPTN) as part of a wider agreement to help develop Indonesia's aviation industry. Within ten years, manufacture of the Bo 105 had been entirely localised within IPTN's own facilities.[26] The Bo 105 has been used by various branches of the Indonesian National Armed Forces; military-operated Bo 105s have been reportedly used during the 1999 East Timorese crisis and the Papua conflict.[27] Indonesian Bo 105s have also participated in several large-scale joint exercises.[28][29]

The Mexican Navy operated a number of armed Bo 105s to perform maritime reconnaissance duties; during the early 1980s, Mexico procured a number of a Uribe-class patrol vessels which were equipped to handle the Bo 105 for off-shore operations.[30] In 2005, work was completed on a series of upgrades upon 11 of the Mexican Navy's Bo 105s, having received Forward looking infrared (FLIR) sensors, Global Positioning System (GPS) receivers, search radars, new rotor blades, armament pylons, and other changes.[31] In November 2014, Jet Rescue Air Ambulance inaugurated Mexico's first dedicated civil air ambulance rotorcraft using a Bo 105.[32]

A Mexican Navy Bo 105 onboard USS Yorktown, 2002

During the late 1990s, the Republic of Korea Army aviation procured a number of Bo 105s as part of an ongoing drive to improve the force's reconnaissance and surveillance capabilities; these were manufactured under a co-production arrangement between Eurocopter and the newly formed Korea Aerospace Industries (KAI), receiving the designation Korean Light Helicopter (KLH), KAI also promoted the type to export customers.[33][34]

The Bo 105 gained widespread use by emergency medical service (EMS) / medevac operators; in 1998, Flying Magazine reported that between the Bo 105 and the MBB/Kawasaki BK 117 (a newer rotorcraft derived from the Bo 105), MBB held 35% of the EMS market share.[35] The first EMS-orientated Bo 105 in Scotland entered service in 1989; in November 2015, the last Bo 105 air ambulance operated in Britain was retired, the type having typically been replaced by the newer Eurocopter EC135.[36] In 2009, the last Bo 105 to be produced was purchased by Canadian EMS specialist Dam Helicopters.[37][38]

In May 2014, Airbus Helicopter reported that the worldwide Bo 105 had accumulated a total of 8 million flight hours, and that approximately 700 Bo 105s remained in service.[39]

Variants

1974

The variants used by the German Army are the Bo 105P and Bo 105M.

  • Bo 105A : First production model primarily for civil use and equipped with two Allison 250-C18 turbine engines.
  • Bo 105C : Initial version. Developed in 1972 and equipped with two Allison 250-C20 turbines engines.[12]
  • Bo 105CB : Light observation, utility transport version. Developed in 1976 and equipped with two Allison 250-C20B turbine engines of which 30 were delivered to The Royal Netherlands Air Force.[12]
Russian MBB Bo 105 at HeliRussia 2008
  • Bo 105CBS : Utility transport version, with the fuselage stretched by 10 inches and an extra window for emergency medical service duties.[12]
  • Bo 105CBS-5 : Also known as Superfive, with increase lifting capabilities similar to the LS A3 Superlifter
  • Bo 105D : UK certified offshore version.
  • Bo 105LS A1 : Developed in 1984 with stretched fuselage and two Allison 250-C28C turbine engines.
  • Bo 105LS A3 : Developed in 1986 with maximum take-off weight increased to 2,600 kg.
  • Bo 105LS A3 "Superlifter" : Developed in 1995 with maximum mission weight increased to 2,850 kg.
  • Bo 105P/PAH-1 : With its army designation "PAH-1" and "PAH-1A1" for the upgraded version (PAH=Panzerabwehrhubschrauber; 'Tank-defence helicopter'), is an anti-tank helicopter armed with wire-guided HOT ATGMs (HOT2 for the upgraded A1 version).[12] Following the arrival of the Eurocopter Tiger attack helicopter, some were retired while others disarmed and downgraded to the VBH version for continued service.
  • Bo 105P/PAH-1A1 : Improved anti-tank version for the German Army, fitted with six HOT missile tubes.[12]
  • Bo 105P/PAH-1 Phase 2 : Proposed night attack version for the German Army.[12]
  • Bo 105P/BSH Proposed escort version for the German Army, armed with Stinger air-to-air missiles.[12]
  • Bo 105M : With its army designation "VBH" (Verbindungshubschrauber; 'liaison chopper'), is a light transport and surveillance helicopter.[12] They were outphased and replaced by disarmed and modified PAH1.
  • Bo 105/Ophelia : Test and trials aircraft fitted with a mast-mounted sight.[12]
  • Bo 105ATH : Anti-tank version for the Spanish Army.[12]
  • Bo 105GSH : Armed scout version for the Spanish Army.[12]
  • Bo 105LOH : Observation version for the Spanish Army.[12]
  • Bo 105MSS : Maritime version, fitted a search radar.
  • NBO-105 : Were Manufactured by IPTN under licence from MBB (now Eurocopter) 1976–2011; only rotors and transmission now supplied by Germany; originally NBO-105 CB, but stretched NBO-105 CBS available from 101st aircraft onwards. 122 were produced, Dirgantara Indonesia stopped production in 2008.
  • Bo 105S : Search and rescue version.
  • NBO-105S : Stretched version.
  • Bo 105 Executaire: Boeing Vertol and Carson Helicopters manufactured a 24.5 cm stretched version of the Bo 105 under license as the Executaire in an attempt to break into the U.S. light helicopter market, but sales were dismal.[40]
  • Bo 105E-4 : 12 German Army Bo 105P upgraded and overhauled for a 10 million euro contract and donated to Albania first batch delivered in 2006, the helicopters have better performance and avionics. The conversion of other Bo 105 helicopters from the German Armed Forces is also under consideration with a view to future sales.[41]
  • EC-Super Five : High performance version of the Bo 105CBS.
  • Bo 105 KLH : license-produced combat version of CBS-5 custom-fitted with Korean mission equipment package including communication, navigation, electronic warfare and target acquisition system,[42] to meet Republic of Korea Army's operational requirements. KLH also has greatly improved rotor blade and transmission system. 12 are in service.
  • Bo 106 : Widened cabin to seat 7 instead of 5. First flight was on 26 September 1973.[43] A single helicopter of that variant has been made (registration D-HDCI, serial no. 84). The Bo 106 was also equipped with more powerful Allison 250 C 20B engines. In 1981, the German air rescue organization Deutsche Rettungsflugwacht/DRF Luftrettung bought that prototype and had it rebuilt into a 105 CB-2 with a standard cabin. It flew for DRF until November 1993 under the registration D-HCCC, but in 1994 it was put aside to gain spare parts for another DRF helicopter (Bo 105 CBS-S, registration D-HNNN, serial number 662).

Operators

Military

The first Bo 105E-4 that entered service with the Albanian Air Brigade, 2006
 Albania
 Bahrain
 Brunei
 Chile
 Colombia
 Germany
German Army Bo 105P in flight
 Indonesia
 Lesotho
 Mexico
 Peru
 Philippines
 South Korea
A Philippine Navy Bo 105C helicopter used in Search and Rescue, recon & liaison duties
 Spain
 Uruguay

Government and civilian

 Argentina
 Canada
 Chile
 Germany
A Indonesian Navy Bo105 landing on the flight deck of USS Fort Worth, 2015
 Netherlands
 South Africa
 Spain

Former operators

 Chile
 Ciskei
 Iraq
 Netherlands
 Nigeria
 Philippines
 Sierra Leone
 Sweden
A Bo 105 CBS of the German Federal police
 Trinidad and Tobago
 United Arab Emirates
 United States

Accidents and incidents

  • 24 July 1991 - A Bo 105 went down at the Nevada Test Site, killing 5.[70][71]
  • 2 February 1995 - A Bo 105CB crashed and burned in Indonesia after the pilot lost control due to engine failure while cruising; the accident killed two and injured one.[72]
  • 24 May 2002 - A Bo 105 operating in the UK crashed at sea after the load it was airlifting shifted and struck the tail rotor.[73]
  • 2 October 2005 – A Bo 105S, operated by AMS Air Ambulance, crashed into a mountain side in the Western Cape, South Africa while evacuating a road accident patient. The crash was fatal to all 4 occupants of the craft.[74]
  • December 2005 - A Bo 105 owned by the Canadian Coast Guard crashed off the coast of Newfoundland, Canada, leaving two individuals dead.[75]
  • 19 June 2008 - 4 military personnel died in a crash involving a Bo 105 above Bosnia-Herzegovina.[76]
  • 18 June 2010 - A Bo 105 of the Argentinian TV channel C5N, crashed into a suburban area, at the outskirts of Buenos Aires. The pilot and a cameraman died in the accident. The cause of the crash was to be determined after further investigation.[77]
  • 15 December 2011 - A Bo 105 crashed on a parking lot in the southern Venezuelan city of Ciudad Guayana during a test flight. An aeronautical technician died and the pilot was injured.[78]
  • 9 September 2013 - A Bo 105 owned by the Canadian Coast Guard crashed in the Arctic, leaving three dead. The aircraft was assigned to the Canadian Coast Guard Ship Amundsen, a research vessel and icebreaker.[79]

Specifications (Bo 105CB)

MBB Bo 105.png
Cockpit of a Bo 105
External video
video icon Documentary on Bo 105P PAH1 attack helicopter
video icon Bo 105 performing acrobatic display

Data from Jane's All the World's Aircraft 1988-89 [80]

General characteristics

Performance

Armament

See also

Related development
Aircraft of comparable role, configuration and era
Related lists

References

Citations

  1. 1.0 1.1 1.2 Lua error in package.lua at line 80: module 'strict' not found.
  2. 2.0 2.1 Weeghman 1975, p. 54.
  3. 3.0 3.1 Moll 1991, p. 105.
  4. Moll 1991, p. 96.
  5. looping capability according to the German Air Force museum at Gatow
  6. Moll 1991, pp. 103-104.
  7. 7.0 7.1 7.2 Rieck, Joan M. "Bölkow's Bo105." Flight International, 18 May 1967, p. 794.
  8. 8.0 8.1 8.2 8.3 8.4 8.5 8.6 8.7 Gotzhein, Christina. "Eurocopter celebrates the 40th Anniversary of the Maiden Flight of the BO105, the World’s first light twin-turbine Production Helicopter." Eurocopter, 15 February 2007.
  9. Taylor 1976, p. 73.
  10. Air International May 1976, p. 246.
  11. "A Marriage that Lasted." Flight International, p. 30. 31 May 2004.
  12. 12.00 12.01 12.02 12.03 12.04 12.05 12.06 12.07 12.08 12.09 12.10 12.11 12.12 Stemp 2012, p. 339
  13. Lua error in package.lua at line 80: module 'strict' not found.
  14. Wise, Jeff. "How to Fly a Helicopter—Upside Down." Popular Mechanics, 25 May 2012.
  15. Weeghman 1975, pp. 54-56.
  16. 16.0 16.1 Moll 1991, p. 101.
  17. 17.0 17.1 Moll 1991, p. 103.
  18. 18.0 18.1 Moll 1991, p. 104.
  19. Moll 1991, pp. 98, 101.
  20. 20.0 20.1 Weeghman 1975, p. 56.
  21. Moll 1991, p. 98.
  22. Moll 1991, pp. 102-103.
  23. Weeghman 1975, p. 57.
  24. "Characteristics of the Messerschmitt-Bolkow-Blohm (BO-105-CBS) helicopter." Canadian Coast Guard, Retrieved: 6 November 2015.
  25. Krotz 2011, pp. 59-61.
  26. Amir 2012, p. 106.
  27. "STOP Arming Indonesia." European Network Against Arms Trade, 1994.
  28. Keck, Zachary. "Indonesia to Conduct Massive Military Drill." The Diplomat, 21 May 2014.
  29. Rahmat, Ridzwan. "Indonesian navy conducts first helicopter landing on USN LCS." IHS Jane's Navy International, 18 August 2015.
  30. "Mexico Study: Chapter 5. National Security." marines.mil, Retrieved: 1 November 2015.
  31. "Procument, Mexico." Jane's Sentinel Security Assessment , 11 February 2011.
  32. "First full HEMS for Mexico." AirMed & Rescue Magazine, 26 November 2014.
  33. Moon, Chung-in. and Jin-Young Lee. "The Revolution in Military Affairs and the Defence Industry in South Korea." Security Challenges, vol. 4, no. 4. (Summer 2008), pp. 117-134.
  34. Doyle, Andrew. "KAI aims high." Flight International, 9 October 2001.
  35. "EMS Safety Record Soars." Flying Magazine, December 1988. Vol. 115, No. 12. p. 11.
  36. "'End of an era' as last Bolkow air ambulance to retire." BBC News, 24 September 2015.
  37. Careless, James. "Dam Good." Helicopters Magazine, 30 June 2009.
  38. "Dam Helicopters Inc. takes to the sky with the last new BO105 LS." Airbus Helicopters , 1 June 2009.
  39. "BO105 Continues as Workhorse, Topping 8 Million Hours." Rotor & Wing, 27 May 2014.
  40. Lua error in package.lua at line 80: module 'strict' not found. translated from German by Google translate
  41. EADS N.V. - Eurocopter to deliver 12 BO 105 helicopters to the Albanian Defense Ministry
  42. Lua error in package.lua at line 80: module 'strict' not found.
  43. Flug Revue, issue January 1974, p. 4.
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  70. http://articles.latimes.com/1991-07-26/news/mn-255_1_helicopter-crash
  71. http://community.seattletimes.nwsource.com/archive/?date=19910725&slug=1296387
  72. http://aviation-safety.net/wikibase/wiki.php?id=32290
  73. http://www.aaib.gov.uk/cms_resources.cfm?file=/dft_avsafety_pdf_023445.pdf
  74. Lua error in package.lua at line 80: module 'strict' not found.
  75. http://www.cbc.ca/news/canada/investigation-begins-into-newfoundland-helicopter-crash-1.566620
  76. http://news.xinhuanet.com/english/2008-06/20/content_8403923.htm
  77. Lua error in package.lua at line 80: module 'strict' not found.
  78. Lua error in package.lua at line 80: module 'strict' not found.
  79. http://www.cbc.ca/news/canada/north/story/2013/09/10/north-chopper-crash.html
  80. Taylor 1988, pp. 93—94.

Bibliography

  • Amir, Sulfikar. "The Technological State in Indonesia: The Co-constitution of High Technology and Authoritarian Politics." Routledge, 2012. ISBN 1-13618-958-0.
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  • Stemp, P. D. "Kites, Birds & Stuff - Aircraft of Germany: Volume 2 - E to H." Lulu, 2012. ISBN 1-29129-268-3.
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  • Weeghman, Robert B. "Boeing's Tuetonic Twin." Flying Magazine, April 1975, Vol. 96, No. 4. pp. 54–57.
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External links