In 1973, Bell initiated design of a stretched Bell 206 JetRanger in response to pressures from the marketplace for a light single-engine turbine helicopter with more seating. The stretch added only 1.7 feet to the aft cabin, but allowed installation of two seats canted slightly towards the centerline. This increased seating capacity to seven and allowed a more private cabin for four or five passengers behind the pilot. This proved to be an instant hit and spawned a second marketing success for Bell by providing the air charter, corporate and EMS operators with a cost-effective helicopter.
The original LongRanger, the Bell 206L, used an upgraded transmission and the new “Nodamatic” transmission mounting. This reduced the vibration level in the cabin but it used the same engine as the Bell 206B, the 250-C20. This provided only indifferent performance and, in short order, Bell upgraded the engine to the more powerful 250-C28 model, improved the transmission, and installed a new tail rotor to handle the increased torque. At the same time, they redesigned the deck where the engine and transmission are mounted. They also provided the system redundancy required for IFR certification. The Bell 206L1 proved to have very satisfactory performance, even under hot and high conditions. Subsequent improvements saw the installation of a more powerful engine, the 250-C30P, another upgrade to the transmission, and several increases in maximum takeoff gross weight.
The design of the Bell 206L1 used the same proven two-bladed teetering rotor used on the Bell 206 Jet Ranger but with a larger diameter. The engine used on the Bell 206L1 is the Rolls-Royce 250-C28. As an option, the 250-C30P engine from the Bell 206L3 can also be used. A two-bladed tail rotor provides directional control and the main and tail rotor blades use an extruded aluminum spar with a honeycomb core and bonded skin. The fuselage is made of conventional aluminum alloy. The cabin has two seats in front and an aft cabin with two seats facing aft and a three-seat bench facing forward. The cabin is long enough to allow carrying of two stretchers, one on top of the other, on one side of the cabin. This leaves room for two medical attendants. As with the Bell 206, a skid landing gear is used for the sake of simplicity.
Design of the Bell 206L was launched in 1973 and the 206L1 was launched two years later in 1975. The first flight of the Bell 206L1 took place in 1976. Certification was received in 1978 and IFR certification was achieved about six months later. Deliveries started the same year and continued until 1982, when this model was superseded by the Bell 206L3. Over 600 206L1s were delivered during this time.