Exhibition
Bölkow Bo-105B
Designer & manufacturer:
Eurocopter Deutschland (formerly MBB); marketing address: Eurocopter International, 10 Avenue Marcel Cachin, BP 107, F-93123 La Courneuve Cedex, France. Fax: +33 (0)1 49 344530.
Category & usage:
Light twin-engined multi-purpose helicopter for civil, paramilitary and armed military missions. Used especially in SAR/EMS and police missions, as well as in military missions as VBH ("connection helicopter") and PAH ("anti-tank helicopter").
Other single types and projects:
Bo-106: Version with wider (50 cm/19.7 in) main cabin module; Allison 250 C20B; seven-seated; first flight: 25 September, 1973; only 1 prototype.
Bo-105HGH: ("high-speed helicopter"). Developed from V2 prototype by an extensive aerodynamic modification. Compound helicopter with large aerofoils. It reached a speed of 404 km/h in 1975.
Bo-115: Project of a typical anti-tank helicopter with dynamic components of the Bo-105 and a new slim fuselage with two-seated tandem cockpit. 1975 suspended.
Bo-105: “flying laboratory“ which was used for long-lasting tests of experimental avionics, visionics, and control systems. E.g., the optical TV-IR system OPHELIA and an AEG surveillance radar (both above the rotor), a terrain-avoidance radar, electronic "fly-by-wire" control with a cyclical sidestick, and a "fly-by-light" tail-rotor control. In May 1995, the aircraft was lost in an accident and will be replaced by an EC-135.
Programme aspects:
Serial production since 1970, today in the Donauwörth plant of Eurocopter Deutschland (formerly MBB) and (MBB)/Eurocopter Canada in Fort Erie, Ontario (54 LS versions until now). Licence production: at CASA in Spain, PADC in the Philippines (36 helicopters). In Indonesia, IPTN has been building NBo-105 versions since 1976; so far more than 123 helicopters for the domestic market as well as for the export market. By May 1997, more than 1425 Bo-105 helicopters of all versions had been built by MBB/Eurocopter and its licensees.
Coverage:
Some of the many customers worldwide: Bundesgrenzschutz (Federal Border Guard), Germany: 23 + 17 CBS-5; Canadian Coast Guard: 16 CB; Allgemeiner Deutscher Automobil-Club (ADAC): 7 CBS; Deutsche Rettungsflugwacht (German Air Rescue): 11 CBS; Schweizerische Rettungsflugwacht (Swiss Air Rescue) REGA: 3 CBS; Norsk Luftambulanse (N): 7 CBS; EMERCOM Russia (Ministry for Civil Defense, Emergencies and Elimination of Consequences of Natural Disasters): 4 CBS-5; Czech police; ERA Helicopters (USA): 24 CBS; Petroleum Helicopters (USA): 22. Military operators: Bundeswehr Heeresflieger (Army Aviation): 100 Bo-105M (VBH) + 212 Bei 05P (PAH1). Bahrain; Brunei; Chile; Indonesia: 40 (from IPTN production); Iraq: 40 C (some subsequently configured as PAH); Jordania (from IPTN production); Kenya; Columbia (marine); Lesotho; Mexico (marine): 12; Netherlands: 30 C as VBH; Nigeria: 30 (SAR); Peru: 11 LS; Philippines: 14 C; Sweden: 20 CB (PAH/TOW) + 4 CBS (SAR); Spain (army), 73 in 3 versions from CASA production: 29 HA. 15 (PAH/HCT), 33 HR.15 (with gun under fuselage), 11 HE.15 (VBH); Sudan; Tanzania; Trinidad & Tobago; United Arab Emirates.
Details
Powerplant:Two Rolls Royce Allison 250 free-power turbines. These are arranged diagonally outward with 14° each.
Gearbox:
Designed and produced by Zahnradfabrik Friedrichshafen (ZF). Three-stage main gear with one planetary stage.
Main rotor:
Counter-clockwise, fixed with four manually foldable blades, rotary speed: 424 rpm. Tip speed: 218 m/s. Fixed rotor-head system Bölkow with forged rigid titanium hub, finished all sides. Internal crosswise steel-shim disc pack sandwich for centrifugal force transmission. The blades from GRP with PVC hard-foam core and titanium erosion-control plate around the blade nose are certified for a service life of more than 10,000 h in torsion: -8° linear. They are designed with a pitch angle varied when bended in impact direction. The effect of vertical gusts are automatically reduced. Vibrations are dampened in the transition phase by double-pendulum vibration absorbers on each blade stem.
Tail rotor:
Semi-rigid with two GRP blades, lower edge in forward direction (the prototypes had the blades running with the lower edge in reverse direction, which was aerodynamically less favourable). Rotary speed: 2,220 rpm. Tip speed: 221 m/s. Central delta flapping hinge. The ground clearance of the tail rotor of 2 m is an essential safety issue with regard to danger of life on the ground and to landings in rough terrain or in remote areas.
Fuselage:
Conventional light-metal semi-shell construction with non-load bearing components from GFK (doors and cowlings). The transition between fuselage and tailboom with an inevitably adverse aerodynamical design caused by the rear cargo doors produced a wake vortex repeatedly changing from left to right (Kármán vortex street). As a consequence, the machine showed the tendency of oscillating around the yaw axis. This phenomenon could be eliminated by applying a fixed spoiler to the bottom of the fuselage tail.
Cockpit/cabin:
Max. six-seated. Standard: 2 front seats, rear seating bench with 3 seats. One folding door on each side for the front seats and one sliding door on each side for the rear seats. Two rear "Clamshell" cargo doors facilitate fast and easy loading of the rear cargo compartment. Its height is only 0.57 m (22 in), but it is open to the cabin and allows to transport even long and protruding goods. The CS, CBS and LS versions have a cabin length of 25 cm more with only 25 kg additional empty mass, but they provide a significant comfort enhancement for passengers.
Landing gear:
Landing skids. Optional: four emergency floats.
Systems and equipment:
The Bo-105 was the first helicopter in its class to receive redundant hydraulic and electric systems.
Specific characteristic: The bending-moment transmission capacity of the Bölkow rotor may exceed the stress limit of the rotor mast. Therefore, a mast bending-moment indicator is a standard equipment of the Bo-105. When hovering, this instrument directly indicates, whether the balance point of the machine is within permissible limits. Optional equipment: There is a great variety of optional equipment available, e.g.: dual controls; FR instrumentation; weather radar; load hook; rescue hoist; WSPS; long-range auxiliary tank; engine-air sand filter; external loudspeaker; comprehensive EMS intensive-care equipment; VIP interior design.
Armament options:
Great variety, e.g.: guns, fire-and-forget missiles, anti-tank guided missiles: Euromissile HDT or Hughes TOW with corresponding telescopic sight units.
History
Until World War II, the German helicopter technology under Henrich FOCKE and Anton FLETTNER had reached a leading position worldwide. In 1945 the Allies imposed a mandatory break on this new branch as well. It was ten years after the end of World War II that BÖLKOW Entwicklungen KG started to engage also in the helicopter sector. In the meantime, rotocraft revolution had been making great progress in other countries, and in those days it was not easy for Dr.-Ing. Ludwig BÖLKOW and his small team to catch up with helicopter technology and particularly find a gap in the market. One of the former Bölkow projects was the development of fibre-glass-reinforced plastic blades for the Bo-102 and Bo-103 types, which had turned out to be extremely promising. Their high elasticity and durability seemed to make it possible to implement a viable fixed rotor with a rigid rotor head. This new rotor was used for the first time in 1961, when the Bo-104 project for a small double-seated helicopter driven by two 88-shp rotary engines was developed. It was in the same year that Bölkow decided to suspend the Bo-104 in favour of the Bo-105 project following a market analysis. Bölkow came to the conclusion that only a larger helicopter with an entirely new concept would have the chance to assert itself among the types of the established manufacturers. The following design concept was chosen for the Bo-105 to stand out positively from the competitors. Double-engined, fixed rotor with GRP blades, high tail rotor, high safety standards by redundant systems, special appropriateness for rescue operations; ease of maintenance and high component durability. The Federal Government granted a loan to implement the project covering 60% of the development costs to be refundable in the event of a commercial success. Chief engineer Emil Weiland, the intellectual father of the Bo-105, headed a great part of its development, before he died in 1981. The new rotor had its first run on a Merckle SM67 helicopter tied on the ground. After Sud Aviation had acquired a licence for the fixed Bölkow rotor and its GRP blades, a three-bladed version was successfully tested in 1966 in Marignane on an ALOUETTE II during 300 flight hours. The prototype V-1 was primarily destined to be used for cell and power transmission tests. For reasons of risk limitation, it was equipped with the proven Westland SCOUT articulated rotor; it was, however, completely destroyed by ground resonance before the first flight test. This was a bad experience, which many helicopter manufacturers had to endure. The positive results gained with the GLR Alouette II allowed to equip already the V-2 with the new rotor. Its first flight with a duration of 18 minutes was on 16 February, 1967, with chief test pilot Baron Wilfried von Engelhardt at the controls. The early testing gave positive results so that the machine could make its debut on the Paris Air Show in 1967, after only 14 hours flight time. Originally, the Allison 250 C18 turbines were only an alternative solution. On 20 December, 1967, prototype V-3 started, equipped with two MAN turbo 5 6022 with a take-off power of 280 shp each. This new German tandem-compound turbine was suspended later in favour of the proven Allison 250. In May 1969, the company became part of the new Messerschmitt-Bölkow-Blohm (MBB) group. In October 1970, the MBB Bo-105A received its German LBA type rating and only a few months later its FAA type rating.Ten Bo-105 that were rented, and later bought, from Heeresfliegerversuchsstaffel 910 were undergoing an intensive large-scale test for more than four years. As a consequence, the Bo-105M was commissioned in 1974, as successor of the ALOUETTE II (VBH), and the Bo-105P as first-generation PAH (PAH-1). In 1975, Franklin Carson presented the Bo-105 "EXECUTAIRE" version, stretched by 25.4 cm (10 in). This modification developed by Carson Helicopters Inc. (USA) in collaboration with Boeing Vertol was then adopted by MBB for the Bo-105CS, CBS and LS versions. In 1989, the Heeresfliegerwaffenschule Bückeburg conducted extensive field tests with four escort-helicopter prototypes. After this, 54 Bo-105M/VBH were selected to be converted into BSH-1, armed with air-to-air STINGER guided missiles. However, after the collapse of the Warsaw Pact, it was decided to renounce the BSH-1 and an upgrading program planned for the PAH-1.
In 1992, the Bo-105 became part of the EUROCOPTER helicopter series after the fusion of the rotocraft sectors of DASA (formerly MBB) and Aérospatiale. Since then, some of the technical innovations originating from the PAH-1 upgrading program, e.g., the new and more efficient rotor blades, have been used on the latest Bo-105CBS-5 SUPER FIVE (1994) and Bo-105LS-AR SUPER LIFTER (1995) versions.
The Bo-105 was not the first production helicopter with GRP blades, as is often claimed. This was Kamov’s Ka-26. But it was the first helicopter with a fixed rotor and the first light two-engined helicopter to reach serial production. The "Bölkow rotor" proved to be a technological pioneer work, even it had been outdated by newer concepts. The fact that the Bo-105 is still in production even 30 years after its first flight and 25 years after its operational introduction makes it a "classic in its own time".
Technical Data
| Version | CB | CBS | CBS-5 | |
| Dimensions: | ||||
| Overall length | m | 11.86 | 11.86 | 11.86 |
| Overall height | m | 3.02 | 3.02 | 3.02 |
| Fuselage length | m | 8.56 | 8.81 | 8.81 |
| Main rotor diameter | m | 9,84 | 9,84 | 9,84 |
| Tail rotor diameter | m | 1.90 | 1.90 | 1.90 |
| Masses: | ||||
| Max. take-off mass | kg | 2,400 | 2,400 | 2,500 |
| Max. take-off mass with external load | kg | 2,400 | 2,400 | 2,400 |
| Empty mass | kg | 1,245 | 1,269 | 1,320 |
| Powerplant: | ||||
| Turbines | 2x Allison 250 C20B | 2x Allison 250 C20B | 2x Allison 250 C20SuperB | |
| Turbine power TOP, AEO (total) |
kW | 626 | 626 | 626 |
| Flight performance and limits: | ||||
| Max. speed | km/h | 270 | 270 | 270 |
| Cruise speed | km/h | 242 | 242 | 243 |
| Max. climb rate | m/s | 8 | 8 | 8.2 |
| Max. range | km | 575 | 575 | 564 |
| Max. endurance | h | 3.5 | 3.5 | 3.5 |
| Hover ceiling (IGE) | m | 2,560 | 2,560 | 2,438 |
| Hover ceiling (OGE) | m | 1,615 | 1,615 | 1,628 |
| Service ceiling (approved) | m | 5,182 | 5,182 | 5,182 |
B-105 Versions
| Version | Turbine version | MTOM [kg] | Registration year | Remarks |
| Bo-105 V1 | Allison 250 C18 | 2000 | Prototype 1, destroyed by ground resonance. Rotor by Westland SCOUT | |
| Bo-105 V2 | Allison 250 C18 | 2000 | D-HECA, first prototype flying | |
| Bo-105 V3 (Bo-105B) | MAN 6022B | 2000 | Prototype 3 / displayed in Hubschraubermuseum Bückeburg | |
| Bo-105 V4 | Allison 250 C18 | 2000 | Prototype 4, used for authorization flights | |
| Bo-105 V5 | Allison 250 C18 | 2000 | Prototype 5, for Boeing Vertol | |
| Bo-105 V6 | Fracture cell for static load tests | |||
| Bo-105 S1 - SB | Allison 250 C18 | 2100 | Pre-production series | |
| Bo-105A | Allison 250 C18 | 2100 | 1970 | First production lot |
| Bo-105C | Allison 250 C20 | 2100 | 1971 | |
| Bo-105D | Allison 250 C20B | 2300 | 1972 (CAA) | Especially for FR operation in UK. Otherwise like CB |
| Bo-105CB | Allison 250 C20B | 2300 | 1976 | |
| Bo-105CS | Allison 250 C20 | 2300 | 1977 | |
| Bo-105M | Allison 250 C20B | 2300 | 1978 | VBH for Bundeswehr Heeresflieger (Army Aviation) |
| Bo-105P | Allison 250 C20B | 2400 | 1979 | PAH1 for Bundeswehr Heeresflieger (Army Aviation) |
| Bo-105CBS | Allison 250 C20B | 2400 | 1980 | |
| Bo-105L | Allison 250 C28C | More powerful turbines & gearbox, otherwise like Bo-105CB | ||
| Bo-105LS | Allison 250 C28C | 2400 2600* | 1984 | More powerful turbines & gearbox, otherwise like Bo-105CBS |
| Bo-105LS A-3 | Allison 250 C28C | 2600 | Hot & high version | |
| Bo-105LS B-1 | P & W PW2OSB (prototype) | Prototype (reg. C-FMCL) 1988 built & tested in Canada | ||
| HKP-9A** | Allison 250 C20B | 2400 | Similar to Bo-105CB. PAH for Swedish army with Saab Emerson HELI-TOW PAL system | |
| HKP-9B** | Allison 250 C20B | 2400 | Similar to Bo-105CBS. SAR version for Swedish air force | |
| Bo-105CBS-5 Super Five |
Allison 250 C20B | 2500 | 1994 | New rotor blades, stronger main gearbox, more single-engine power (Cat. A) |
| Bo-105LS-AR Super Lifter |
Allison 250 C28C | 2600 2850* | 1995 | New rotor blades, tail rotor from BK117 C-1 |
