Origins of the project

After the commercial success achieved with the Bell 206A Jet Ranger (followed in 1972 by the higher-performance Bell 206B Jet Ranger II), on September 25, 1973 Bell Helicopter announced that it was developing a new, larger and romier helicopter derived from the Jet Ranger.
With seating for one pilot and six passengers, the new model was developed to provide an intermediate capacity option between the five-seat Jet Ranger and the Bell 205A-1, which could carry up to 14 passengers in addition to the pilot.
To provide the necessary comfort for passengers seated behind the cockpit, the fuselage was lengthened by 25 inches (63.5 cm), a modification already adopted by some manufacturers such as Hiller (Hiller UH-12E4) and the lesser-known Carson Helicopter Inc. of Perkasie, Pennsylvania, which developed the Carson Super C-4 derived from the Bell 47G/G2. The LongRanger — this being the name chosen for the new model — was easily distinguishable from its predecessor by the additional window inserted in the central fuselage section.
An important innovation, introduced for the first time by the American manufacturer on this model, was hidden beneath the upper cowling above the cabin. The main transmission was in fact attached to the fuselage by means of an ingenious vibration-damping mechanism that connects the transmission to the airframe through elastomeric mounts. The system uses two main beams to support the transmission, allowing the fuselage to remain stable even when the rotor vibrates at high frequencies.
The Nodamatic transmission suspension system (also known as nodal beam suspension), patented by Bell and described in detail later on, isolates the vibrations generated by the rotor, significantly reducing noise and vibrations in the cabin for a smoother flight, an aspect that is particularly important in two-bladed helicopters.
To compensate for the increase in weight, the helicopter was equipped with the more powerful Allison Model 250C-20B engine, capable of developing a maximum takeoff power of 420 hp (instead of 317 hp as on the Jet Ranger) and a maximum continuous power of 276/370 kw/shp.
The transmission was redesigned to absorb a maximum takeoff power of 420 hp and a maximum continuous power of 276/370 kw/shp.
Further modifications concerned the main and tail rotors whose diameter was increased. Fuel capacity was increased by 22 U.S. gallons (83 liters), for a total of 98 gallons (371 liters).

The first prototype of the Bell 206L LongRanger, registered N206L (c/n 45001), performed its maiden test flight on September 11, 1974 at the company’s plant in Hurst, Texas. According to available research, other prototypes were prepared for testing.

Certification and first deliveries

In a press release issued on January 4, 1974, Bell’s then Vice President of Commercial Sales, Dwayne K. Jose, announced that the helicopter would be marketed the following year.
By early 1975, each prototype had accumulated approximately 100 flight hours. Up to that point, only a few maintenance-related issues had been encountered. Maintenance accessibility was significantly improved compared to the 206B. For example, on the 206L it was no longer necessary to disconnect the exhaust duct in order to remove the engine cowling.
On September 22, 1975, the Bell 206L LongRanger received Federal Aviation Administration certification.
Deliveries of the first production aircraft to operators began at the end of October 1975.
The base price of the Bell 206L LongRanger was 250,000$ (by comparison, the Bell 206B JetRanger was sold for 170,000$).
Operators immediately showed interest in the LongRanger’s features, but it soon became apparent that the power provided by the engine was rather limited and that performance was not particularly impressive, especially at maximum take-off weight, at altitude, or in hot and humid environments such as the Gulf of Mexico. The LongRanger was in fact proposed, among its various roles, for offshore operations.
Low operating costs and the addition of two extra cabin seats contributed to the widespread adoption of this model among operators offering sightseeing flights.
For the same reasons, economy and cabin space, the helicopter also began to be used as an air ambulance.
In Europe, the German steel manufacturing company Benteler Werke AG, based in Schloss Neuhaus/Paderborn, has been the first to receive the new Bell 206L LongRanger. The helicopter was used to transport executives and customers.

Over the years, new versions were introduced, differing mainly in their engine type. The models are: 

• Bell 206L-1 LongRanger II – produced from 1978 onward (Allison 250-C28 – greater power than the initial version and improved performance in “hot and high” conditions);
• Bell 206L-3 LongRanger III – produced from 1981 onward (Allison 250-C30P – further increase in power and overall performance improvements);
• Bell 206L-4 LongRanger IV – produced from 1992 to 2017 (Allison 250-C30P – similar to the L-3 but with an increased maximum takeoff weight and structural and avionics upgrades); 

Production of the LongRanger began in Texas but later moved when Bell inaugurated its plant in Mirabel, Canada. From 1987 onward, starting with the aircraft bearing serial number 51215, all LongRangers were manufactured in Canada.
Series production ended in 2018, after a long period of coexistence with the Bell 407, which has been in production since 1996.

A “magic potion” to boost power

Like the Gauls in the Asterix series, the Bell 206L LongRanger also had its own “magic potion” that provided it with extra power, certainly not superhuman, as in the case of the characters from the famous comic series. This came in the form of the standard water-alcohol power augmentation kit.
The system consisted of a 3-gallon tank (approximately 11 liters), equipped with a filler cap and adapter assembly, as well as a pressure relief valve and a T-fitting. A mounting bracket was installed at the bottom of the tank, supporting a float switch. A filter was mounted at the base of the tank. The system also included a solenoid valve, a pressure switch, a manifold, and a control switch. At critical moments, especially during takeoff, when extra power was required, the pilot could inject a mixture of distilled water and methyl alcohol (66.5% water and 33.5% alcohol) into the compressor. This reduced the temperature of the compressor discharge gases, allowing the use of higher torque. The system used engine bleed air to force the mixture into the compressor.

The evaporation of the water-alcohol mixture cooled the incoming air and increased its density; this resulted in greater mass flow and improved compressor efficiency. According to the 206L flight manual, with a full water-methanol tank the total available operating time was approximately three minutes. 
When the quantity of mixture in the tank decreased to about half a gallon (1.9 liters), the amber W/A LOW LEVEL warning light illuminated. At that point, the pilot was required to reduce power within 30 seconds to avoid exceeding the maximum allowable temperature, which in maximum continuous power is 810°C.
For this reason, the device was generally used only for the strictly necessary time. The pilot had to monitor the TOT, N1, and TRQ instruments and adjust power to maintain the prescribed limits. At that stage, the pilot was required to reduce power and then place the W/A INJECT switch to OFF. The green “FLOW LIGHT” illuminated indicated that there was no flow.
Over the years, several operators removed this system (previously available as an optional kit for the Bell 206A JetRanger equipped with a C-18B turbine) and converted the original C-20B turbine to the more powerful C-20R/2 version, increasing output by 22/30 kW/shp (from 309/420 kW/shp to 331/450).

Alert Service Bulletin (ASB)

Among the features that distinguish the LongRanger from the JetRanger at a glance — besides the additional window — are the two vertical endplates mounted on the horizontal stabilizer. These were not present on the first production units.
As often happens when a new aircraft enters the market, operators of the Bell 206L LongRanger began reporting a number of issues to the manufacturer, some of which concerned the horizontal stabilizer. Its function is to ensure adequate pitch control of the helicopter depending on speed, weight, center of gravity, and applied power.
Among the reported issues was the appearance of fine cracks in the stabilizer itself, particularly in attachment areas and in zones subject to greater stress.

A review of the original maintenance manual dated September 22, 1975, revealed the following.
The Alert Service Bulletin (ASB 206L 78-3 – Inspection of Horizontal Stabilizer), issued on October 23, 1978, required operators to inspect the horizontal stabilizer (P/N 206-023-119) to assess its condition and identify possible problems.

An ASB is a communication from the manufacturer to operators highlighting:

• potential safety or reliability issues;

• recommended pre-flight inspections;

• required replacements or checks;

• possible temporary modifications pending more permanent solutions;

Unlike a standard Service Bulletin (SB), an ASB is considered more urgent and addresses issues that may have a direct impact on in-service safety.
For this specific horizontal stabilizer issue, ASB 206L 80-16 — Inspection of horizontal stabilizer assembly, P/N 206-023-119 — followed on November 17, 1980, requiring inspection of the horizontal stabilizer assembly on all 206L LongRanger helicopters to verify structural integrity.
Subsequently, ASB 206L 81-23 — Modification or retirement of horizontal stabilizer assembly, dated July 10, 1981, and later revised on October 23, 1981 (Revision A), mandated the modification or retirement of the horizontal stabilizer assembly on Models 206L and 206L-1.
The modification of the horizontal stabilizer on the Bell 206L LongRanger involved eliminating the original moveable elevator linked to the cyclic control and adopting a fixed aerodynamic configuration. This change applied both to aircraft in production and to helicopters already in service, for which a Supplemental Type Certificate (STC) was issued—an official approval granted by the aviation authority (in the United States, the FAA) authorizing a modification to an already certificated aircraft, its engine, propeller, or component. Operators were required to modify or replace non-compliant stabilizers no later than 25 flight hours after March 31, 1982. By doing so, the helicopter maintained its required standards of safety and aerodynamic reliability.

A successful series

Starting in mid-1978 the 206L was replaced by the 206L-1 version, which was powered by the more powerful Allison 250-C28B turboshaft, delivering a maximum continuous power of 373/500 kW/shp, a transmission capable of absorbing greater power, and various additional improvements.
Production of the LongRanger began in Texas but was relocated when Bell Helicopter inaugurated its facility in Mirabel, Canada. Beginning in 1987, with serial number 51215, all LongRangers were manufactured in Canada.
In 2007, Bell Helicopter announced an upgrade program for the 206L-1 and 206L-3 models. The modifications included reinforced structural airframe components — among them a new tailboom — an improved transmission, and a more powerful engine for the L-1 version.
With the introduction of the Bell 407 (which received Federal Aviation Administration certification on February 9, 1996), regarded as the direct successor to the LongRanger and occupying the same market segment, series production of the latter first declined and was ultimately discontinued in June 2017, when serial number 52496 rolled off the Mirabel assembly line.
This aircraft was part of a batch destined for a single operator, the U.S. air medical service Air Evac Lifeteam.

A significant portion of 206L-4 production was absorbed by this major customer, which during the final six years acquired 49 of the 69 aircraft manufactured.
The LongRanger, in its various versions (206L, 206L-1, 206L-3, and 206L-4), remained in production for more than 40 years and achieved considerable commercial success.
The 206L-1 and 206L-3 models can both be modified to the 206L-4 configuration (designated respectively as 206L-1+ and 206L-3+) in accordance with Bell Kit 206-706-530.
In conclusion, it can be stated that the 206L LongRanger undoubtedly contributed to the commercial success of the Bell 407.
Bell continues to manufacture LongRanger dynamic components, which are used in the new Bell 505 Jet Ranger X.

The twin-engine that never took off

In the first half of the 1980s, Bell Helicopter developed a twin-engine version derived from the LongRanger, designated the Bell 400 TwinRanger. The lukewarm interest shown by operators led the manufacturer to shelve plans for series production. Subsequently, the California-based company Tridair Helicopters developed an STC for a twin-engine conversion of the 206L, known as the Gemini ST.

Based on the Bell 206L-4 LongRanger IV, this led to the creation of the Bell 206LT TwinRanger.
Operators’ initial doubts were soon confirmed: the twin-engine version did not achieve commercial success, and only three Gemini ST conversions and 14 examples of the 206LT were built.

Technical Description

The fuselage of the Bell 206L LongRanger consists of three main sections:

1. Cabin (or forward) section

The cabin is the forward section, extending from the nose to the bulkhead located behind the passenger compartment. It includes the crew and passenger compartments, fuel cell installations, and pylon support fittings.
The primary load-bearing elements are made of aluminum honeycomb structure with fiberglass fabric skins. The basic structure consists of a lower-curved sandwich panel and an upper longitudinal aluminum beam with a honeycomb core and an upper longitudinal aluminum beam.
The core of the sandwich structure is aluminum alloy throughout, and is faced with aluminum alloy except in the fuel cell region, where fiberglass is used. The rotor, transmission and engine are supported by the upper longitudinal beam, which is connected to lower structure by three fuselage bulkheads and a centerpost to form an integrated structure. The most forward and aft bulkheads act as carry-through structure for the landing gear crosstubes;

2. Intermediate (or center) section

The intermediate section extends from the bulkhead aft of the passenger compartment to the tailboom attachment point. It includes the baggage compartment and the heater compartment and is of semi-monocoque construction. Titanium and aluminum alloy panels provide a deck for the power plant assembly, oil tank, oil cooler, and oil cooler blower;

3. Tailboom

The tailboom is full monocoque construction with aluminum skin and substructure. It supports the horizontal stabilizer, vertical fin, tail rotor driveshaft, and tail rotor gearbox with associated fairings. It is attached to the center section by four bolts;

With a cabin volume of 2.35 m³ (88 cubic feet), compared to 1.39 m³ (49 cubic feet) of the Bell 206B JetRanger, functionality on the Bell 206L LongRanger was significantly improved through innovative solutions designed to make maximum use of the available space. For example, the front left passenger seat features a folding seatback to allow the loading of a container measuring 2.44 × 0.91 × 0.30 m (8 × 3 × 1 ft), making it possible to carry bulky equipment internally.
The double doors on the left side of the cabin provide an opening 1.52 m (5 ft) wide, allowing easy direct loading of patient stretchers or cargo. In air ambulance configuration, the aircraft can carry two stretcher patients plus two seated patients or attendants.
With a two-person crew, the standard cabin layout accommodates five passengers, seated on two aft-facing seats angled 10° inward and three forward-facing seats. A storage compartment is integrated into an armrest located between the two aft-facing seats.

An executive configuration with four individual passenger seats was also available. The cabin is soundproofed and equipped with three ashtrays, map holders, a fire extinguisher, a first aid kit, and a storage shelf above the rear seatbacks. It features a forced-air ventilation and defogging system.
The cabin is enclosed by a tinted acrylic windshield and six side windows, with sliding ventilation panels on the four doors. The upper windows are made of tinted polycarbonate.
Further detail improvements included a redesign of the instrument panel, pedestal, and glare shield to provide the pilot with improved visibility over the nose and through the lower forward windows.
All instruments are located in the central instrument panel which is visible to both pilots and observer. The basic “T” flight group arrangment is provided for standardisation. Visibility forward of the cabin is excellent due to the low, compact panel which is a itself an extension of the vertical central column and the radio console which continues forward as the structural support to the forward electronics compartment.
In the intermediate section, behind the passenger cabin, a readily accessible and lockable baggage compartment with a capacity of 453 liters (16 cubic feet) can accommodate up to 113.4 kg (250 lb) of cargo and/or baggage.
The tailboom, attached to the center section of the Bell 206L LongRanger, consists of an aluminum alloy monocoque structure supporting the tail rotor drive system, as well as the horizontal stabilizer, vertical fin, and the tail rotor and driveshaft fairings.
The vertical fin, constructed with an aluminum honeycomb core and aluminum alloy skin, is offset 4° to the right to reduce tail rotor load during cruise flight. The vertical fin contrains a top fairing for mounting the anti-collision light, and and on the lower edge a rubber bumper and tail skid are installed in the event of a nose-up landing attitude.
The fixed horizontal stabilizer, featuring an inverted asymmetric airfoil profile, generate a downward force in cruise flight that helps maintain the passenger cabin in a nearly level attitude.

The two vertical endplates mounted at the outer ends of the horizontal stabilizer are slightly offset to the left and counteract the coupled oscillatory motion involving yaw and roll, which affects the helicopter’s lateral and directional stability.
The enclosed transmission components are accessible through hinged inspection panels. A retractable step provides access to the upper work platform.

Engine

Originally the Bell 206L LongRanger was equipped with an Allison 250-C20B turboshaft engine, the third-generation version of the 250 series. It combined proven features with extended Time Between Overhaul (TBO) intervals for many of its modular components. Engine intake air is directed to the combustion section at the aft end of the engine. Fuel is mixed with the compressed air and the mixture ignited. The exhaust gases are directed forward through the turbines and upward and overboard through two exhaust stacks. 
Compared to earlier variants, the C-20B features increased airflow through both the compressor and turbine, higher operating temperatures, and more advanced Honeywell/Bendix fuel control systems, resulting in improved overall performance.
The engine delivers a maximum takeoff power (limited to 5 minutes) of 313/420 kW/shp at 105% N1 (53,519 rpm), and a maximum continuous power of 276/370 kW/shp.
It features a modular design with a 6-stage axial-flow compressor and a single-stage centrifugal compressor, a 2-stage gas generator turbine, and a 2-stage free power turbine, offering a power-to-weight ratio of 2.7:1 and high reliability.
The engine is installed aft of the mast and transmission on top of the aft fuselage above the intermediate section of the fuselage.

Beneath the engine is a titanium deck that serves both as a drip pan for possible fluid leaks and as a heat insulator. Fuel consumption is approximately 100 liters (26 U.S. gallons) per hour of kerosene. The engine weighs 72 kg including essential accessories but excluding the starter-generator.

Fuel system

Fuel storage consists of three interconnected fuel cells. The main tank, with a capacity of 76 U.S. gallons (288 liters), is located beneath and behind the three-passenger rear seat bench. Two additional fuel cells (each holding 11 gallons, or 46.6 liters) are installed beneath the cabin floor, under the two aft-facing passenger seat. Total fuel capacity is therefore 98 U.S. gallons (371 liters). The three fuel cells are made of non-self-sealing rubberized fabric. They are secured in place by nylon lacing and fitted with molded metal inserts at openings and internal component passages. A transfer pump moves fuel from the forward cells to the aft cell whenever one of the fuel pumps is operating. With the optional “range extender” installation — essentially a 90-degree curved tube mounted on the original filler neck — fuel capacity is increased to 110 U.S. gallons (416.4 liters).
The kerosene tanks are filled through a single filler port located on the right side of the cabin, behind the passenger cabin door.

Transmission and power train

The main transmission is mounted forward of the engine and is coupled to the engine by means of a short driveshaft. At 100% power, this shaft rotates at 6,016 rpm. The main transmission was upgraded to fully utilize the increased engine power.
Basically the transmission is a reduction gear box which transmits engine power, at reduced rpm, to the main rotor by means of a pair of spiral bevel gears and a planetary gear stage (a two-stage reduction gearbox with a reduction ratio of 15,228:1), main rotor speed is reduced to 395 rpm. The transmission incorporates a self-contained lubrication system with an oil cooler mounted directly on the gearbox. Provisions are included for mounting and driving the hydraulic pump and the rotor tachometer. A one-way sprag-type freewheling unit is mounted on the engine gear box. During autorotation the freewheeling unit provides a disconnection from the engine and allows autorotational forces of the main rotor to drive the transmission, tail rotor and all transmission driven accessories.
The transmission is secured by the Nodamatic isolation system which minimizes airframe vibration and permits higher flight speeds without compromising pilot confort of the fatigue life of the aircrame and dymamic parts. A sight gauge is provided to check the oil level. An oil filter with replaceable cartridge eliminates any damaging contaminants.
The main rotor mast is tilted 3° forward and 1.5° to the left to facilitate lift-off, help counter translating tendency, and maintain the passenger cabin in a nearly level attitude during cruise flight.
The tail rotor 90° gear box consists of two spiral bevel gears which provide a 2,35:1 rpm reduction (from 6,000 to 2,550 rpm), an oil reservoir sight gauge and a magnetic chip detector. The magnetic drain plug and sight gauge are easily accessible from ground level.
The tail rotor drive shaft consists of six sections, four of which are identical. Only the forward section and the tail gear box coupling are different. Five sealed, permanently lubricated, hanger bearings support the tail rotor drive shaft between the cooling fan and the tail rotor gear box.

The Nodamatic

In the Bell 206L LongRanger, the transmission is mounted using the Nodamatic isolation system. Here’s how it works: all vibration waves have “nodes,” points where no motion occurs. Keeping this principle in mind, engineers at Bell Helicopter designed the LongRanger fuselage to be suspended only at these nodal points.

By supporting the structure at the vibration nodes, rotor-induced vibrations are effectively isolated, making flight significantly more comfortable — especially during high-speed cruise and maneuvering — while also reducing stress on the airframe and dynamic components.
The transmission features a visual oil level indicator, and a replaceable cartridge oil filter removes harmful contaminants.

Main rotor

The Bell 206L LongRanger features a two-bladed, semi-rigid, "teetering" main rotor system with a 11,28 m (37 ft) diameter, which is 22 inches longer than the 206B JetRanger. The interchangeable blades have a 33,02 m (1 ft 1 in chord), 11° negative twist, and tapered tips to improve aerodynamic performance. They are all-metal construction, with an aluminum alloy spar, spar spacer, trailing-edge strip, and honeycomb core, and aluminum skins. All structural components are connected via metal-to-metal joints. A trim tab on the trailing edge allows for blade tracking adjustments. Hight blade inertia, the most important aspect of good autorotation characteristics, is provided by 9,98 kg (22 pounds) of weight distributed linearly in the leading edge.
Rotor speed is approximately 394 rpm. 

Tail rotor

Directional control is provided by a two-blade, semi-rigid tail rotor mounted on the left side of the tailboom in a pusher configuration. Viewed from the left side of the helicopter, it rotates clockwise. The tail rotor diameter is 1,676 m (5 ft 6 in).
The fuselage extension, longer main rotor blades, and increased engine power required a redesigned and improved tail rotor gearbox. The new mounting system, using load-bearing pins, also reduces maintenance time.
The 206L tail rotor blades (profile NACA 0012) are longer than those installed on the JetRanger. The driveshaft support bearing can be lubricated in the field.
The tail rotor hub and blade assembly consist of a forged aluminum alloy fork and strong steel/aluminum blades, each individually interchangeable. Leading edges are reinforced with stainless steel strips, and the core is a honeycomb filler. Each blade contains two dry spherical bearings installed in an aluminum alloy retention block to provide for pitch change movement. The non-adjustable pitch links also use maintenance-free bearings. At its introduction, the tail rotor design had a proven safety record with over 7 million flight hours.

Flight Controls

The flight control system of the Bell 206L LongRanger consists of push-pull control tubes and bellcrank. The cyclic and collective control systems incorporate hydraulic servo actuators installed on the cabin roof forward of the transmission that utilizes irreversible valves to minimize control force feedback, even in turbulent air. Fixed lenght control tubes and a minimum of adjustabletubes simplify rigging. All self aligning bearing and rod ends are spherical bearings and require no lubrication. Access doors located on the aft side of control column and removable seats are provided for control inspection and maintenance accessibility. Access doors are provided at the rear of the control column, and seats are removable to facilitate inspection and maintenance of the control linkages.

Landing gear

The forward and aft cabin bulkheads serve as structural attachment points for the transverse landing gear tubes. The standard landing gear is skid-type, made from tubular aluminum alloy with replaceable steel wear strips mounted beneath the skids. Fairings are installed on both transverse tubes. The helicopter can be equipped with various landing gear configurations, including: standard low skids, high skids, fixed floats, or emergency self-inflating floats. For ground handling, wheels can be attached at the balance point of the skids. A hydraulic system, operated by a lever, raises and lowers the wheels.

Electrical system

The helicopter is equipped with a 28V DC electrical system. The helicopter electrical power is provided by a nickel-cadmium battery located in the nose section, a starter-generator and an external power receptacle.

Accessories

Over the years, the Bell 206L LongRanger offered a wide range of optional accessories, including: high skids landing gear, dual controls, rotor brake, fixed floats and emergency floats, bear paws, particle separator, auto re-light kit, fire extinguisher, cable cutter, snow deflectors for turbine air intakes, cabin heating, pilot and co-pilot shoulder harnesses, stretchers, cargo hook (capacity 907 kg / 2,000 lb) with mirrors, bubble windows, auxiliary battery, external cargo basket, flight instrument package, avionics and communications/navigation equipment, custom interiors, first aid kit, fuel range extender, maintenance steps, bleed air defroster kit, clock, spray kit and many other optional items.

Performance

The following table summarizes the performance of the Bell 206L LongRanger powered by an Allison 250 C-20B in function of the take-off weight:

Dimensions and weight

The approximate empty weight of the LongRanger is 955 kg (2,105 lb), varying depending on installed equipment. Maximum takeoff weight is 1,814 kg (4,000 lb), whether carrying internal or external loads.

Civil applications

The Bell 206L LongRanger has been used primarily for passenger and cargo transport, offshore operations, medical emergency services, sightseeing flights, corporate personnel transport, forestry crew transport, firefighting support, aerial surveillance and police missions, aerial photography and filming, aerial crop treatments.

The Bell 206L LongRanger in Switzerland

Two Bell 206L LongRanger were imported into Switzerland through the Geneva-based Transair, a company that served as the Swiss representative for several aeronautical brands. One of the very first production-built aircraft (serial number 45013, manufactured in 1975) received the civil registration HB-XFK and was entered in the aircraft register on February 3, 1976. In September 1976 it was used by the police of the Canton of Bern as an aerial observation post.

On that occasion, a prominent sticker bearing the word “Police” appeared on its fuselage. On December 6 of the same year, after being sold to a new Austrian operator, it was cancelled from the Swiss aircraft register. 

The guru and the helicopter

The second aircraft, serial number 45025, was imported in the spring of 1976 and was assigned the registration HB-XFV by the Federal Office of Civil Aviation on May 15, 1976. After remaining registered for a few months in the name of Transair, on September 15, 1976 it was registered in the name of its new owner, VLTM which stands for Verein für die Lehre der Transzendentalen Meditation (Association for the Teaching of Transcendental Meditation).
Associations for Transcendental Meditation in Switzerland emerged in the wake of the international spread of this meditation technique founded by Maharishi Mahesh Yogi. The latter developed and standardized the practice of yoga in the 1950s and 1960s, bringing it from India to the West and creating a network of teachers and organizations dedicated to its dissemination in many countries, including Switzerland. While passing through Switzerland one day, the guru became fascinated by the mountain village of Seelisberg in the Canton of Uri, located just above the Rütli meadow, often referred to as the "cradle of Switzerland" or the founding site of Switzerland and is of great national importance. Enchanted by the surrounding landscape, the tranquility, and the view over the mountains and Lake Lucerne, in the early 1970s he moved the international headquarters of the movement there, establishing it the former Grand Hotel Sonnenberg. Thanks to the growing wealth of the movement, the VLTM indulged in the luxury of purchasing the LongRanger to enable the guru to travel between various headquarters and meditation centers scattered throughout Switzerland and Europe.

On November 23, 1976, while en route from Seelisberg to Unterseen near Interlaken, the helicopter suffered an unexpected power loss. The pilot skillfully executed an autorotation, bringing the aircraft down in a clearing on the southern shore of Lake Brienz. The landing resulted in damage to the landing gear, however neither occupant was injured. The aircraft was subsequently recovered by a Heliswiss-operated helicopter and flown to the Bohag facility in Interlaken, then loaded on a truck and trasferred to Belp (BE) to be repaired by Heliswiss’s maintenance service.
The subsequent post-accident investigation revealed that the engine complete loss of power had been caused by fatigue failure of the 3 ^rd stage turbine wheel. 
HB-XFV was removed from the Swiss aircraft register on February 7, 1979, after being sold to Canada, where it continued flying under the new registration C-GXKA.

Did you know…

The company Air Evac Lifeteam, an American company founded in 1985 by a group of citizens from West Plains and now part of Global Medical Response, operated 130 LongRangers.
Air Evac Lifeteam is the largest independently owned and operated air ambulance service in the United States, supported by a membership program, with more than 150 interconnected bases that support one another across 15 states.

The Bell 206L-1 LongRanger II N3911Z holds the distinction of being the first helicopter to complete a round-the-world flight.
The helicopter, in standard configuration, was specially modified for the long journey. The modifications took three weeks and included the installation of an additional 151 U.S. gallons (571 liters) fuel tank, a Loral radar, a modified heating/defrosting system, inflatable emergency floats, as well as special safety, communication, and navigation equipment.