Tag Archives: Bell Helicopter Company

2 October 1970

October 2, 2024Aviation1st Special Operations Wing, 31001, 40th Helicopter Squadron, 68-10772, 9, Bell 212, Bell Helicopter Company, Bell Model 212, Bell UH-1N Iroquois, Helicopter, Hurlburt Field, Pratt & Whitney Canada PT6T-3 Twin-Pac, Pratt & Whitney Canada T400-CP-400, Twin Huey, Twin Pac, Two-Twelve Twin, UH-1N-BFBryan Swopes

The very first UH-1N, 68-10772, photographed in March 2012. (© Ralph Duenas. Photograph used with permission.) — The very first U.S. Air Force UH-1N Iroquois, 68-10772, photographed March 2012. (© Ralph Duenas. Photograph used with permission.)

2 October 1970: The U.S. Air Force 1st Special Operations Wing at Hurlburt Field, Florida (Eglin AFB Auxiliary Field #9), took possession of the very first Bell UH-IN Iroquois, UH-1N-BF 68-10772 (Bell Helicopter Co. serial number 31001).

Also known as the “Twin Huey,” the medium-lift helicopter is a two-engine version of the Bell Model 205 (UH-1H). Originally developed for the Canadian Forces as the Bell Model 212, the UH-1N is powered by a Pratt & Whitney T400-CP-400 (the military designation for the commercial PT6T-3 “Twin-Pac”) which consists of two PT6 turboshaft engines mated to a combining gearbox to drive a single output shaft to the helicopter’s main transmission. The combined unit can produce a maximum 1,800 shaft horsepower. If one engine fails, the remaining engine can operate at 900 shaft horsepower for 30 minutes. The T400 is de-rated to the main transmission limit of 1,290 shaft horsepower.

The helicopter has other improvements over the Model 205/UH-1D/H Huey. The main rotor blades have a wider chord, producing greater lift. The main transmission is rated for greater power input. The tail boom and tail rotor pylon are strengthened, and the tail rotor has been moved to the opposite side of the pylon, in a tractor configuration instead of the previous pusher configuration. The tail rotor blade rotation is reversed with the advancing blade moving upward into the down flow of the main rotor, making it more efficient. Visual differences are the streamlined nose and the reshaped “dog house” covering the twin engine installation.

Cockpit of a U.S. Air Force/Bell UH-1N Iroquois during a 60° bank. (A1C Nigel Sandridge, U.S. Air Force) — Cockpit of a U.S. Air Force/Bell UH-1N Iroquois during a 60° right bank. (A1C Nigel Sandridge, U.S. Air Force)

The U.S. Air Force normally operates the UH-1N with two pilots and a flight engineer, but it can be flown by a single pilot under visual weather conditions, if necessary. It is capable of transporting up to 12 passengers in addition to the three-man crew.

The Bell Helicopter Co. UH-1N Iroquois (Model 212) is 57 feet, 3 inches (17.450 meters) long, with a main rotor diameter of 48 feet, 0 inches (14.630 meters) and tail rotor diameter of 8 feet, 6 inches (2.591 meters). The overall height of the helicopter is 12 feet, 10 inches (3.912 meters) and the fuselage has a maximum width of 9 feet, 5 inches (2.870 meters). The helicopter’s empty weight is 6,032 pounds (2,736 kilograms), depending on installed equipment. The maximum takeoff weight is 10,500 pounds (4,763 kilograms).

The Pratt & Whitney Canada T400-CP-400 has a maximum continuous power rating of 1,530 shaft horsepower at 6,600 r.p.m. at Sea Level.

The helicopter’s cruise speed is 110 knots (127 miles per hour/204 kilometers per hour) and the maximum speed is 128 knots (147 miles per hour/237 kilometers per hour) at Sea Level. The UH-1N has an out-of-ground-effect hover ceiling (HOGE) of 13,000 feet (3,962 meters). The service ceiling is 21,600 feet (6,584 meters). The combat radius is 105 nautical miles (121 statute miles/194 kilometers) maximum ferry range is 565 nautical miles (650 statute miles/1,046 kilometers).

U.S. Air Force Bell UH-1N Iroquois helicopters deploy security personnel. (U.S. Air Force)

The UH-1N can be armed with GAU-16 .50-caliber machine guns or GAU-17 7.62mm “miniguns.”

The UH-1N is operated by the Air Force, the U.S. Navy and Marine Corps, as well as many foreign military services. In civil use, the Bell 212 is the most common medium lift helicopter worldwide and has been for 54 years.

Of the 79 UH-1N helicopters ordered by the U.S. Air Force in 1968, 59 remain in active service (as of September 2015). On 18 March 2024, a UH-1N assigned to the 58th Operations Group, Det 2, at Kirtland Air Force Base, New Mexico, the Air Force’s UH-1N training unit, 69-6650 logged its 20,000th flight hour.

On 24 September 2018, the U.S. Air Force announced that it would replace the UH-1N fleet with 84 Boeing/Leonardo MH-139A Grey Wolfs, with the first aircraft being delivered in 2021. In actuality, the first field-read MH-139A arrived at Malmstrom Air Force Base in Montana in March 2024.

Still in service, UH-1N 68-10772 was photographed in flight 4 May 2022 at Gowen Field, Boise, Idaho. The helicopter was painted in the Southeast Asia camouflage scheme of the 20th Special Operations Squadron, “Green Hornets.”

This rear quarter view of UH-1N-BF 68-10776 of the 40th Helicopter Squadron, flying across Montana, shows the two exhaust ducts of the PT6T-3 Twin Pac. This helicopter, Bell serial number 31005, was the fifth UH-1N built. (U.S. Air Force)

Bell UH-1N-BF 69-6615, 40th Helicopter Squadron, in the Front Range of the Rocky Mountains. (Senior Airman Eydie Sakura, U.S. Air Force)

The very first Bell UH-1N, 68-10772, was photographed at Gowen Field, Boise, Idaho, on 4 May 2022, by Sean Asay. The helicopter is shown in the Southeast Asia camouflage scheme of the 20th Special Operations Squadron, “Green Hornets.” (Photograph © Sean Asay. Used with permission.)

30 September 1982

September 30, 2024Aviation45658, Allison 250-C28B, Allison Division of General Motors, Around-The-World-Flight, Bell 206L-1 LongRanger II, Bell Helicopter Company, Circumnavigation, H. Ross Perot Jr., Helicopter, Jay Coburn, N3911Z, NASM, National Air and Space Museum, Smithsonian Institution, Steven V. Udvar-Hazy CenterBryan Swopes

H. Ross Perot, Jr. and Jay W. Coburn with Bell 206L-1 LongRanger II, N3911Z, after their 29-day around-the-world flight. (© Bettman/Corbis)

30 September 1982: H. Ross Perot, Jr. and Jay W. Coburn completed their around-the-world helicopter flight when they landed Spirit of Texas at their starting point at Dallas, Texas. They had flown the single-engine Bell 206L-1 LongRanger II, serial number 45658, civil registration N3911Z, more than 26,000 miles (41,843 kilometers) in 246.5 flight hours over 29 days, 3 hours and 8 minutes.

They had begun their journey 1 September 1982. Perot and Coburn traveled across twenty-six countries. They established a Fédération Aéronautique Internationale (FAI) record for helicopter speed around the world, eastbound, having averaged 56.97 kilometers per hour (35.399 miles per hour). (Class E-1d, FAI Record File Number 1254). They also established a series of point-to-point records while enroute, with the highest speed, an average of 179.39 kilometers per hour (111.47 miles per hour), taking place on 7 September 1982, while flying Spirit of Texas from London to Marseilles (FAI Record File Number 10018).

The Bell Helicopter Company Model 206L-1 LongRanger II is a 7-place light helicopter developed from the earlier 5-place Model 206B JetRanger series. It is designed to be flown by a single pilot in the right front seat, and is certified for Visual Flight Rules.

The 206L-1 is 42 feet, 8 inches (13.005 meters) long, overall, and 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 37 feet (11.278 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 11° negative twist. The blade tips are swept.

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 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 LongRanger II is powered by an Allison 250-C28B turboshaft engine. This engine produces 500 shaft horsepower but is de-rated to 435 horsepower, the limit of the main transmission. The engine is mounted above the roof of the fuselage, to the rear of the main transmission. Output shafts lead forward to the transmission and the tail rotor drive shaft aft to the tail rotor 90° gear box. The transmission and rotor mast are mounted angled slightly forward and to the right. 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. Vertical fins are attached to the outboard ends of the horizontal stabilizers and above the tailboom centerline. The fins are slightly offset to the left and counteract the helicopter’s Dutch roll tendency.

The helicopter has an empty weight of approximately 2,160 pounds (979 kilograms), depending on installed equipment, and the maximum gross weight is 4,050 pounds (1,836 kilograms).

The Model 206L LongRanger first flew in 1974 and the 206L-1 LongRanger II variant entered production in 1978. It was replaced several years later by the 206L-3. The LongRanger remains in production as the Model 206L-4.

Perot had purchased the LongRanger II for $750,000, specifically for this flight. Modifications started immediately and over the next three weeks an additional 151-gallon fuel tank was added giving the helicopter approximately 8 hours’ endurance. “Pop-out floats”—inflatable pontoons that can be deployed for emergency landings on water—were installed. The helicopter also carried a life raft and other emergency equipment and supplies. Additional communication, navigation equipment and radar was installed.

Spirit of Texas aboard a container ship. — N3911Z aboard a container ship.

During the circumnavigation, the helicopter burned 56,000 pounds (25,400 kilograms) of jet fuel and made 56 fueling stops, including aboard a pre-positioned container ship in the North Pacific Ocean.

The helicopter was donated to the Smithsonian Institution and is on display at the Steven V. Udvar-Hazy Center of the National Air and Space Museum.

Bell 206L-1 LongRanger II s/n 45658, N3911Z, “Spirit of Texas,” on display at the Steven F. Udvar-Hazy Center of the Smithsonian Institution National Air and Space Museum. (NASM)

27 September 1964

September 27, 2024Aviation60-6029, Bell Helicopter Company, Bell YUH-1D Iroquois, c/n 702, FAI, Fédération Aéronautique Internationale, Lycoming T53-L-11, Michael N. Antoniou, White Mountain Research Station, World Record for Distance Without LandingBryan Swopes

Captain Michael N. Antoniou with YUH-1D 60-6029. (FAI)

27 September 1964: Captain Michael N. Antoniou flew the number two Bell YUH-1D-BF Iroquois, 60-6029, Bell Helicopter serial number 702, from Edwards Air Force Base in the high desert of southern California, non-stop to Rogers, Arkansas. The distance flown was 2,170.70 kilometers (1,348.81 miles), and established a Fédération Aéronautique Internationale (FAI) World Record for Distance Without Landing.¹

Captain Antoniou was a project test pilot assigned to the U.S. Army Aviation Test Activity at Edwards.

60-6029 was modified by Bell to reduce aerodynamic drag and weight. The windshield wipers, door handles, main rotor stabilizer bar and associated dampers, tail rotor drive shaft cover and 42° gear box cover had been removed. Gaps at the doors, crew steps, tail boom cargo compartment, etc., were sealed with tape.

The Bell Helicopter Co. UH-1D Iroquois (Model 205) was an improved variant the UH-1B (Model 204). The type’s initial military designation was HU-1, and this resulted in the helicopter being universally known as the “Huey.” The UH-1D has a larger passenger cabin, longer tail boom and increased main rotor diameter.

The UH-1D was a single main rotor/tail rotor medium helicopter powered by a turboshaft engine. It could be flown by a single pilot, but was commonly flown by two pilots in military service. The helicopter had an overall length of 57 feet, 0.67 inches (17.375 meters) with rotors turning. The fuselage was 41 feet, 5 inches (12.624 meters) long. The helicopter had a height of 13 feet, 7.4 inches (4.150 meters), measured to the top of the mast. The maximum gross weight of the UH-1D was 9,500 pounds (4,309.1 kilograms).

The two blade semi-rigid, under-slung main rotor had a diameter of 48 feet, 3.2 inches (14.712 meters), and turned counter clockwise when viewed from above. (The advancing blade is on the helicopter’s right.) At 100% NR, the main rotor turned 324 r.p.m. The two blade tail rotor assembly had a diameter of 8 feet, 6 inches (2.591 meters). It was on the left side of the pylon in a pusher configuration and turned counter-clockwise as seen from the helicopter’s left. (The advancing blade is above the axis of rotation.)

The YUH-1D was powered by a Lycoming T53-L-9 or -11 turboshaft engine which was rated at 1,100 shaft horsepower at 6,610 r.p.m., for takeoff (5 minute limit). The T53-L-11 was a two-shaft free turbine with a 6-stage compressor (5 axial-flow stages, 1 centrifugal-flow stage) and a 2-stage axial-flow turbine (1 high-pressure stage, and 1 low-pressure power turbine stage). As installed in the UH-1, the engine produced 115 pounds of jet thrust (511.55 Newtons) at Military Power.

Its maximum speed, V_NE, was 124 knots (143 miles per hour, 230 kilometers per hour). With full fuel, 206.5 gallons (781.7 liters), the helicopter had a maximum endurance of three hours.

60-6029 was later modified to the prototype YUH-1H.

Captain Michael N. Antoniou with Bell YUH-1D-BF 60-6029 (c/n 702), circa 1965. (David Hatcher Collection)

¹ FAI Record File Number 2180

11 September 1974: TDiA No. 1,500 ¹

September 11, 2024AviationBell 206L LongRanger, Bell Helicopter Company, First Flight, N206LBryan Swopes

Bell Helicopter Company prototype Model 206L LongRanger, N206L. (Vertical Flight Society)

11 September 1974: The first prototype Model 206L made its first flight at the Bell Helicopter Company plant at Hurst, Texas.

Based on the Bell 206B-3 JetRanger III, the LongRanger featured a 30-inch (76.2 centimeters) stretch to the passenger cabin, a lengthened tail boom and longer main rotor blades. It retained the JetRanger’s Allison 250-C20B turboshaft engine.

¹ As of 11 September 2024, This Day in Aviation has published 1,667 articles.

7 September 1965

September 7, 2024Aviation66-15246, Attack Helicopter, Bell AH-1G Cobra, Bell Helicopter Company, Bell Model 209 HueyCobra, Bill Quinlan, First Flight, Helicopter, Lycoming LTC1K-4, Lycoming T53-L-13, M134 Minigun, N209J, Prototype, s/n 20001, Test Flight, Test Pilot, William Thomas QuinlanBryan Swopes

Bell Model 209 prototype, N209J, in flight with skids retracted. (Bell Helicopter Co.) — Bell Model 209, N209J, prototype of the AH-1G Huey Cobra attack helicopter, in flight with landing skids retracted. (Bell Helicopter Company)

7 September 1965: First flight of the prototype Bell Model 209 attack helicopter. Test pilot William Thomas (“Bill”) Quinlan was in command. The duration of the flight was twelve minutes.

The Model 209 was a private venture, built in just seven months and rolled out at Fort Worth, Texas, 2 September 1965. The prototype aircraft combined the drive system, rotors and tail boom of the production UH-1C gunship with a streamlined fuselage which placed the two pilots in tandem.

The prototype was equipped with retractable landing gear which gave the 209 increased speed, but the expense and complexity were enough that this feature was not included on production aircraft.

This helicopter would be developed into the famous AH-1G Huey Cobra.

N209J,the Bell Model 209 prototype, shown in camouflage colors. (Bell Helicopter Company) — N209J, the Bell Model 209 prototype, shown in camouflage colors. (Bell Helicopter Company)

The second prototype, AH-1G 66-15246, was used by the Army for flight testing at Edwards Air Force Base, California, from 3 April to 21 April 1967.

66-15246 had an overall length of 52 feet, 11.65 inches (16.146 meters) with rotors turning. The fuselage was 44 feet, 5.20 inches (13.433 meters) long, and it was 3 feet, 0 inches (0.914 meters) wide. The HueyCobra had a short “stub wing” with a span of 10 feet, 11.60 inches (3.343 meters). Its angle of incidence was 14°. The wing’s area was 27.8 square feet (2.6 square meters). 66-15426 had an empty weight of 5,516 pounds (2,502 kilograms) and maximum gross weight of 9,500 pounds (4,309 kilograms).

Bell Model 209, N209J, prototype of the AH-1G Cobra, with landing skids extended. (U.S. Army)

The two-bladed Model 540 “door-hinge” main rotor was 44 feet, 0 inches (13.411 meters) in diameter. The blades had a chord of 2 feet, 3 inches (0.686 meters) and 10° negative twist. The main rotor turned counter-clockwise when viewed from above. (The advancing blade is on the helicopter’s right.) Normal rotor r.p.m. (power on) was 314–324 r.p.m., and power off, 304–339 r.p.m. The minimum transient rotor speed, power off, was 250 r.p.m.

The two blade tail rotor assembly had a diameter of 8 feet, 6 inches (2.591 meters) with a chord of 8.41 inches (0.214 meters). There was no twist. It was mounted on the left side of the pylon in a pusher configuration and turned counter-clockwise as seen from the helicopter’s left. (The advancing blade is above the axis of rotation.) The tail rotor pylon was cambered to allow aerodynamic forces in forward flight to “unload” the tail rotor.

Bell AH-1G Cobra three-view drawing. (U.S. Army Aviation Systems Test Activity)

The AH-1G was powered by a Lycoming LTC1K-4 (T53-L-13) turboshaft engine rated at 1,400 shaft horsepower, though it was derated to the helicopter’s transmission limit. The T53-L-13 is a two-shaft free turbine with a 6-stage compressor (5 axial-flow stages, 1 centrifugal-flow stage) and a 4-stage axial-flow turbine (2 high-pressure stages, 2 low-pressure power turbine stages). The T53-L-13 is 3 feet, 11.9 inches (1.217 meters) long, 1 foot, 11.0 inches (0.584 meters) in diameter and weighs 549 pounds (249 kilograms).

The speed of the Cobra was effected by the armament configuration, whether “clean,” light or heavy scout, or “heavy hog.” At 5,000 feet (1,524 meters), the cruise speed in the clean configuration was 138.0 knots (158.8 miles per hour, 255.6 kilometers per hour); light scout, 134.0 knots (154.2 miles per hour, 248.2 kilometers per hour); and heavy hog, 127.0 knots (146.2 miles per hour, 235.2 kilometers per hour). The maximum airspeed in level flight was 149.0 knots (171.5 miles per hour, 276.0 kilometers per hour); 144.0 knots (165.7 miles per hour, 266.7 kilometers per hour); and 136.5 knots (157.1 miles per hour, 252.8 kilometers per hour), respectively.

The limiting airspeed (V_NE) was 190 knots (KCAS) (219 miles per hour, 352 kilometers per hour) below 3,000 feet (914 meters) density altitude.

In autorotation, the airspeed for the minimum rate of descent was 74.0 knots (85.2 miles per hour, 137.1 kilometers per hour) with the main rotor turning 294 r.p.m., resulting in a rate of descent of 1,750 feet per minute (8.89 meters per second).

The basic armament for the AH-1G Cobra was an Emerson M28 turret which could be equipped with one or two General Electric M134 Miniguns, or a combination of a Minigun with a Philco Ford M129 automatic grenade launcher, or two grenade launchers. Each Minigun was supplied with 4,000 rounds of 7.62 NATO ammunition, while a grenade launcher had 300 rounds of 40 × 53 millimeter high-velocity explosive ammunition.

Four hardpoints on the stub wing could be loaded with M18 7.62 NATO Minigun pods; XM35 pods, containing a short-barreled General Electric XM195 20 millimeter Gatling gun (a variant of the M61 Vulcan); rocket pods with seven or nineteen 2.75-inch unguided rockets.

The prototype Cobra, Bell Model 209 N209J, is in the collection of the U.S. Army Aviation Museum, Fort Rucker, Alabama, as is the second prototype, 66-15246.