22 July 1983: Richard Harold (“Dick”) Smith landed his Bell JetRanger III helicopter, VH-DIK, at the Bell Helicopter Hurst Heliport (0TE2), in Hurst, Texas, United States of America. He had completed the first solo around-the-world flight by helicopter.
352 days earlier, 5 August 1982, Dick Smith had departed from Hurst on an eastbound circumnavigation. He had purchased the helicopter specifically to make this flight, and named it Australian Explorer. The aircraft, as standard production Bell Model 206B-3, serial number 3653, had been built at the Bell Helicopter TEXTRON plant in Hurst. It was registered VH-DIK by the Australia Department of Aviation, 2 June 1982.
The JetRanger was equipped with a Collins LRN 70 VLF/Omega navigation system, and a Collins autopilot. A larger fuel tank was installed.
Smith’s journey was made in three major segments:
Leg 1: Hurst, Texas, U.S.A., to London, England, from 5 August to 19 August 1982
Leg 2: London, England, to Sydney, New South Wales, Australia, 13 September to 3 October 1982
Leg 3: Sydney, N.S.W., Australia, to Hurst, TX, U.S.A., 25 May to 22 July 1983
The total distance flown was reported in FLIGHT as 32,258 miles (51,914 kilometers). The total flight time was over 260 hours.
Smith’s circumnavigation had also included the first solo flight by helicopter across the Atlantic Ocean. During the journey, he set five separate Fédération Aéronautique Internationale (FAI) world records for Speed Over a Recognized Course. ¹
The Bell JetRanger is a 5-place, single-engine light civil helicopter based on the Bell Helicopter’s unsuccessful OH-4 entrant for the U.S. Army’s Light Observation Helicopter (LOH, or “loach”) contract. It is flown by a single pilot in the right front seat. Dual flight controls can be installed for a second pilot. The helicopter was certified for VFR flight, but could be modified for instrument flight.
The JetRanger is 38 feet, 9.5 inches (11.824 meters) long, overall. On standard skid landing gear the overall height is 9 feet, 4 inches (2.845 meters). The Bell 206A has an empty weight of approximately 1,700 pounds (771 kilograms), depending on installed equipment. The maximum gross weight is 3,200 pounds (1,451.5 kilograms). With an external load suspended from the cargo hook, the maximum gross weight is increased to 3,350 pounds (1,519.5 kilograms).
The two-bladed main rotor is semi-rigid and under-slung, a common feature of Bell’s main rotor design. It has a diameter of 33 feet, 4.0 inches (10.160 meters) and turns counter-clockwise (seen from above) at 394 r.p.m. (100% NR). (The advancing blade is on the helicopter’s right side.) The rotor blade has a chord of 1 foot, 1.0 inches (0.330 meter) and 10° negative twist. The airfoil is symmetrical. The cyclic and collective pitch controls are hydraulically-boosted.
The two-bladed tail rotor assembly is also semi-rigid and is positioned on the left side of the tail boom in a pusher configuration. It turns at 2,550 r.p.m., clockwise, as seen from the helicopter’s left. (The advancing blade is below the axis of rotation.) The tail rotor diameter is 5 feet, 6.0 inches (1.676 meters).
The turboshaft engine is mounted above the roof of the fuselage, to the rear of the main transmission. Output shafts lead forward to the transmission and aft to the tail rotor 90° gear box. The transmission and rotor mast are mounted tilting slightly forward and to the left. This assists in the helicopter’s lift off to a hover, helps to offset its translating tendency, and keeps the passenger cabin in a near-level attitude during cruise flight.
A vertical fin is attached at the aft end of the tail boom. The fin is offset 4° to the right to unload the tail rotor in cruise flight. Fixed horizontal stabilizers with an inverted asymmetric airfoil are attached to the tail boom. In cruise flight, these provide a downward force that keeps the passenger cabin in a near-level attitude.
The 206A was powered by an Allison 250-C18 turboshaft engine (T63-A-700) which produced a maximum of 317 shaft horsepower at 104% N1, 53,164 r.pm. The improved Model 206B JetRanger and 206B-2 JetRanger II used a 370 horsepower 250–C20 engine, and the Model 206B-3 JetRanger III had 250-C20B, -C20J or -C20R engines installed, rated at 420 shaft horsepower at 105% N1, (53,519 r.p.m.). Many 206As were upgraded to 206Bs and they are sometimes referred to as a “206A/B.” The Allison 250-C20B has a 7-stage compressor section with 6-stage axial-flow stages, and 1 centrifugal-flow stage. The 4-stage axial-flow turbine has a 2-stage gas producer (N1) and 2-stage power turbine (N2). These were very light weight engines, ranging from just 141 to 173 pounds (64.0 to 78.5 kilograms).
The helicopter’s main transmission is limited to a maximum input of 317 shaft horsepower (100% Torque, 5-minute limit). The engine’s accessory gear unit reduces the output shaft speed to 6,016 r.p.m. N2, which is further reduced by the transmission’s planetary gears, and the tail rotor 90° gear box.
The JetRanger has a maximum speed, VNE, of 150 miles per hour (241 kilometers per hour) up to 3,000 feet (914 meters). Its best rate of climb, VY, is at 60 miles per hour (97 kilometers per hour) and best speed in autorotation (minimum rate of descent and maximum distance) is at 80 miles per hour (129 kilometers per hour), resulting in a glide ratio of about 4:1. The service ceiling is 13,500 feet (4,145 meters) with the helicopter’s gross weight above 3,000 pounds (1,361 kilograms), and 20,000 feet (6,096 meters) when below 3,000 pounds. The helicopter has a maximum range of 430 miles (692 kilometers).
¹ FAI Record File Numbers 2286, 2287, 2288, 10033 and 10272
© 2018, Bryan R. Swopesby