Tag Archives: Bell Helicopter Company

8 December 1945

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Floyd Carlson, chief Test Pilot for the Bell Aircraft Corporation, hovers the world's first civil-certified helicopter, NC1H, Serial Number One. (Niagara Aerospace Museum)
Floyd William Carlson, Chief Test Pilot, Bell Aircraft Corporation, hovers the world’s first civil-certified helicopter, NC1H, Serial Number One. (Niagara Aerospace Museum)

8 December 1945: At the Bell Aircraft Corporation Wheatfield Plant, Niagara Falls, New York, the first Model 47 helicopter, NX41962, was rolled out. Designed by Arthur M. Young, the Model 47 was based on Young’s earlier Model 30. The new helicopter made its first flight on the same day.

The Civil Aviation Administration (C.A.A.), predecessor of the Federal Aviation Administration, had never certified a helicopter, so Bell worked with government officials to develop civil certification standards. The Bell 47 received the C.A.A. Type Certificate H-1 on 8 March 1946 and the first helicopter’s registration was changed to NC1H.

Bell Model 47 NX41962, Serial Number 1, at Bell’s Wheatfield Plant, early 1946. (Niagara Aerospace Museum)

The Bell 47 series was constructed of a welded tubular steel airframe with a sheet metal cockpit and a characteristic plexiglas bubble. In the original configuration, it had a four-point wheeled landing gear, but this was soon replaced with a tubular skid arrangement. It was a two-place aircraft with dual flight controls.

The first Bell Model 47 had an overall length (with rotors turning) of 39 feet, 7½ inches (12.078 meters). The main rotor diameter was 33 feet, 7 inches (10.236 meters). The length of the fuselage, from the front of the plexiglass bubble canopy to the trailing edge of the tail rotor disc, was 29 feet, 3½ inches (8.928 meters). The tail rotor had a diameter of 5 feet, 5 inches (1.676 meters). The helicopter’s height, to the top of the main rotor mast, was 9 feet, 2-7/16 inches (2.805 meters).

NC1H had an empty weight of 1,393 pounds (632 kilograms). Its gross weight was 2,100 pounds (953 kilograms).

Bell Aircraft Corp. test pilot Floyd W. Carlson demonstrates the stability of the Model 47 by taking his hands off of the flight controls during a hover. (Bell Helicopter)

The Bell 47’s main rotor is a two-bladed, under-slung, semi-rigid assembly that would be a characteristic of helicopters built by Bell for decades. The blades were constructed of laminated wood, and covered with fabric. A stabilizer bar was placed below the hub and linked to the flight controls through hydraulic dampers. This made for a very stable aircraft. The main rotor turns counter-clockwise, as seen from above. (The advancing blade is on the right.) The tail rotor is positioned on the right side of the tail boom in a tractor configuration. It rotates counter-clockwise as seen from the helicopter’s left. (The advancing blade is above the axis of rotation.)

Power was supplied by an air-cooled, normally-aspirated, 333.991-cubic-inch-displacement (5.473 liter) Franklin Engine Company 6V4-178-B3 vertically-opposed six cylinder engine, serial number 17008, rated at 178 horsepower at 3,000 r.p.m. Power was sent through a centrifugal clutch to a transmission which turned the main rotor through a two-stage planetary gear reduction system with a ratio of 9:1. The transmission also drove the tail rotor drive shaft, and through a vee-belt/pulley system, a large fan to provide cooling air for the engine.

The new helicopter had a cruise speed of 75 miles per hour (121 kilometers per hour) and a maximum speed (VNE) of 80 miles per hour (129 kilometers per hour). NC1H had a service ceiling of 11,400 feet (3,475 meters).

The Bell 47 gained fame during the Korean War as a rescue helicopter, transferring wounded soldiers directly to Mobile Army Surgical Hospitals placed near the front lines. Here, a wounded soldier is offloaded from an H-13D-1 Sioux. (U.S. Army)
The Bell 47 gained fame during the Korean War as a rescue helicopter, transferring wounded soldiers directly to Mobile Army Surgical Hospitals placed near the front lines. Here, a wounded soldier is offloaded from an H-13D-1 Sioux. (U.S. Army)
The manufacturer's data plate for Bell Model 47, Serial Number 1. (Niagara Museum of Aeronautics)
The manufacturer’s data plate for Bell Model 47, Serial Number 1. (Niagara Museum of Aeronautics)

The Bell 47 was produced at the plant in New York, and later at Fort Worth, Texas. It was steadily improved and remained in production until 1974. In military service the Model 47 was designated H-13 Sioux, (Army and Air Force), HTL (Navy) and HUG (Coast Guard). The helicopter was also built under license by Agusta, Kawasaki and Westland. More than 7,000 were built worldwide and it is believed that about 10% of those remain in service.

In 2010, the type certificates for all Bell 47 models was transferred to Scott’s Helicopter Service, Le Sueur, Minnesota, which continues to manufacture parts and complete helicopters.

After certification testing and demonstrations, NC1H was one of two Bell 47s used for flight training. The first Bell 47, s/n 1, crashed at Niagara Falls Airport, 3 April 1946.

While hovering out of ground effect, a student inadvertently oversped the main rotor by decreasing collective pitch when he had intended to increase it. The main rotor hub separated and the helicopter dropped to the ground. Both the student and instructor were injured. Damage to NC1H was extensive and the helicopter was scrapped. The registration, NC1H, was reassigned to Bell 47 s/n 11.

Wreck of Bell Model 47 NC1H, s/n 1. (Niagara Aerospace Museum)

© 2018, Bryan R. Swopes

Medal of Honor, Captain James Phillip Fleming, United States Air Force

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1st Lieutenant James P. Fleming, U.S. Air Force, 1968. (Gallery of History, Inc.)
1st Lieutenant James P. Fleming, U.S. Air Force, 26 November 1968. This photograph was taken immediately after landing from the Medal of Honor mission. (Gallery of History, Inc.)

The President of the United States in the name of The Congress takes pleasure in presenting the MEDAL OF HONOR to

CAPTAIN

JAMES PHILLIP FLEMING

AIR FORCE

Rank: Captain
Organization: U.S. Air Force
Division: 20th Special Operations Squadron
Born: 12 March 1943, Sedalia, Mo.
Entered Service At: Pullman, Wash.
Place / Date: Near Duc Co, Republic of Vietnam, 26 November 1968

For service as set forth in the following:

CITATION:

Captain James P. Fleming, U.S. Air Force
Captain James P. Fleming, United States Air Force

“The President of the United States of America, in the name of Congress, takes pleasure in presenting the Medal of Honor to Captain [then First Lieutenant] James Phillip Fleming, United States Air Force, for conspicuous gallantry and intrepidity in action at the risk of his life above and beyond the call of duty while serving with the 20th Special Operations Squadron, 14th Special Operations Wing, in action near Duc Co, Republic of Vietnam, on 26 November 1968. Captain Fleming distinguished himself as the Aircraft Commander of a UH-1F transport helicopter. Captain Fleming went to the aid of a six-man special forces long range reconnaissance patrol that was in danger of being overrun by a large, heavily armed hostile force. Despite the knowledge that one helicopter had been downed by intense hostile fire, Captain Fleming descended, and balanced his helicopter on a river bank with the tail boom hanging over open water. The patrol could not penetrate to the landing site and he was forced to withdraw. Dangerously low on fuel, Captain Fleming repeated his original landing maneuver. Disregarding his own safety, he remained in this exposed position. Hostile fire crashed through his windscreen as the patrol boarded his helicopter. Captain Fleming made a successful takeoff through a barrage of hostile fire and recovered safely at a forward base. Captain Fleming’s profound concern for his fellowmen, and at the risk of his life above and beyond the call of duty are in keeping with the highest traditions of the U.S. Air Force and reflect great credit upon himself and the Armed Forces of his country.”

For a more detailed narrative, see:

http://www.vhpa.org/KIA/panel/battle/68112600.HTM

1st Lieutenant Fleming was presented the Medal of Honor by President Richard M. Nixon in a ceremony at The White House, 14 May 1970.

During his military career, Colonel Fleming had also been awarded the Silver Star, Distinguished Flying Cross and eight Air Medals. He retired from the U.S. Air Force in 1996 after thirty years of service.

The UH-1F was originally tasked with supporting Stratgic Air Command missile bases. (U.S. Air Force)
The UH-1F was originally tasked with supporting Strategic Air Command ICBM missile bases. This helicopter, 66-1235, c/n 7311, was sent to The Boneyard at Davis-Monthan AFB, Arizona, in 1977. It was later registered as a restricted civil aircraft, VH-LIP, used for aerial firefighting by McDermott Aviation, Queensland, Australia,  (U.S. Air Force)

The Bell UH-1F Iroquois (best known as the “Huey”) was was unique to the U.S. Air Force and was initially intended for missile base support. It used the airframe of the UH-1B (Bell Model 204), combined with the 48-foot-diameter main rotor system, transmission and longer tail boom of the UH-1D (Model 205). The Air Force required that it be re-engined to use the General Electric T58-GE-3 turboshaft engine. This was the same engine used in the Sikorsky HH-3E and commonality was desirable, but the T58 was also much more powerful than the Lycoming T53 engine of the UH-1B and UH-1D. The use of the T58 gave the UH-1F/P the distinctive side exhaust exit that identifies it from other Huey variants.

Two U.S. Air Force UH-1P Hueys of the 20th Special Operations Squadron, the "Green Hornets". (U.S. Air Force)
Two U.S. Air Force UH-1P Hueys of the 20th Special Operations Squadron, the “Green Hornets.” 65-7929 is closer to camera. The second Huey is 63-13162. Both helicopters are armed with two door-mounted M93 7.65 mm “miniguns” systems: electrically-driven M134 rotary machine guns capable of a 4,000 round-per-minute rate of fire. On each side of 7929 are 7-tube rocket launchers for 2.75-inch (70 mm) FFAR rockets. (Captain Billie Dee Tedford, United States Air Force)

119 UH-1Fs were built by the Bell Helicopter Co., Fort Worth, Texas. A single-engine, medium-lift helicopter, it is configured to be operated by a pilot and co-pilot and can carry 10 passengers. The first aircraft, originally designated XH-48A, s/n 63-13141, made its first flight 20 February 1964. The first production UH-1F was delivered to the Air Force 23 September 1964. Twenty UH-1Fs were modified to UH-1P as special operations helicopters.

The fuselage of the UH-1F/UH-1P is 44 feet, 7 inches (13.589 meters) long. With blades turning, the overall length of the helicopter is 57 feet, 1 inch (17.399 meters), and it is 14 feet, 11 inches (4.547 meters) high. The main rotor has a diameter of 48 feet, 0 inches (14.630 meters) and turns counter-clockwise as seen from above. (The advancing blade is on the right.) The tail rotor has a diameter of 8 feet, 6 inches (2.591 meters) and is mounted on the left side of the tail boom in a pusher configuration. It turns counter-clockwise as seen from the helicopter’s left. (The advancing blade is above the tail rotor’s axis of rotation.)

20th Special Operations Squadron UH-1P Hueys refueling at Dak To. (Don Joyce/VHPAP.org)
20th Special Operations Squadron UH-1P Hueys refueling at Đắk Tô, Central Highlands, Vietnam. (Don Joyce)

The UH-1F has an empty weight of 4,403 pounds (1,997.2 kilograms), and its maximum gross weight is 9,000 pounds (4,082.3 kilograms).

The UH-1F is powered by a single General Electric T58-GE-3 turboshaft engine. The T58 is an axial-flow engine with a 10-stage compressor, single combustion chamber and 3-stage turbine (2 high- and 1 low-pressure stages. The high-pressure turbine drives the compressor, with a maximum speed of 26,300 r.p.m. (N1). The low-pressure turbine drives the engine’s output shaft, with a maximum r.p.m. of 19,500 r.p.m. (N2). The T-58-GE-3 is rated at 1,070 shaft horsepower, but is capable of producing 1,325 shaft horsepower. The T58 is 4 feet, 7 inches (1.397 meters) long, 1 foot, 8.2 inches (0.513 meters) in diameter, and weighs 305 pounds (138 kilograms).

The UH-1F/P has a maximum speed of  138 miles per hour (222 kilometers per hour), with a normal cruise speed of 123 miles per hour (198 kilometers per hour). It can lift a 4,000 pound (1,814 kilogram) payload. The helicopter has a service ceiling of 24,830 feet (7,568 meters), can hover out of ground effect (HOGE) at 15,700 feet (4,785 meters) and in ground effect (IGE) at 18,700 feet (5,700 meters). With maximum fuel, its range is 392 miles (631 kilometers).

UH-1F and UN-1P helicopters remained in service with the Air Force until the early 1980s when their mission was taken over by the twin-engine UH-1N (Bell Model 212).

Bell Helicopter Corp. UH-1P Iroquois (converted from UH-1F-BF) serial number 64-15476, marked as 1LT James Fleming’s UH-1P, 64-15492, which he was flying during the action of 26 November 1966. The actual 64-15492 was shot down 13 February 1969. This helicopter is in the collection of the National Museum of the United States Air Force. (U.S. Air Force)
Bell Helicopter Corp. UH-1P Iroquois (converted from UH-1F-BF) serial number 64-15476, marked as 1LT James Fleming’s UH-1F, 64-15492, which he was flying during the action of 26 November 1968. The “Green Hornet” of the 20th Special Operations Squadron is painted on the helicopter’s tail boom. The actual 64-15492 (c/n 7042) was shot down 13 February 1969. This helicopter is in the collection of the National Museum of the United States Air Force. (U.S. Air Force)

Coloenel james P. Fleming, U.S. Air Force (Retired) and Mrs. Fleming.
Colonel James P. Fleming, U.S. Air Force (Retired) and Mrs. Fleming. (MSNBC)

© 2018, Bryan R. Swopes

14 November 1965: Medal of Honor, Major Bruce Perry Crandall, United States Army

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Major Bruce Perry Crandall, United States Army
Major Bruce Perry Crandall, United States Army

The President of the United States of America, authorized by Act of Congress, March 3, 1863, has awarded in the name of The Congress the Medal of Honor to

MAJOR BRUCE P. CRANDALL 
UNITED STATES ARMY
for conspicuous gallantry and intrepidity at the risk of his life above and beyond the call of duty:

Rank and Organization: Major, U.S. Army, Company A, 229th Assault Helicopter Battalion, 1st Cavalry Division (Airmobile).

Place and dates: Landing Zone X-Ray, Ia Drang Valley, Republic of Vietnam, 14 November 1965.

Place and date of birth: Olympia, Washington, 1933.

Lieutenant Colonel Bruce P. Crandall, United States Army (Retired), received the Medal of Honor in a ceremony at the White House, Washington, D.C., 26 February 2008. (U.S. Army)

For conspicuous gallantry and intrepidity at the risk of his life above and beyond the call of duty: Major Bruce P. Crandall distinguished himself by extraordinary heroism as a Flight Commander in the Republic of Vietnam, while serving with Company A, 229th Assault Helicopter Battalion, 1st Cavalry Division (Airmobile). On 14 November 1965, his flight of sixteen helicopters was lifting troops for a search and destroy mission from Plei Me, Vietnam, to Landing Zone X-Ray in the Ia Drang Valley. On the fourth troop lift, the airlift began to take enemy fire, and by the time the aircraft had refueled and returned for the next troop lift, the enemy had Landing Zone X-Ray targeted. As Major Crandall and the first eight helicopters landed to discharge troops on his fifth troop lift, his unarmed helicopter came under such intense enemy fire that the ground commander ordered the second flight of eight aircraft to abort their mission. As Major Crandall flew back to Plei Me, his base of operations, he determined that the ground commander of the besieged infantry battalion desperately needed more ammunition. Major Crandall then decided to adjust his base of operations to Artillery Firebase Falcon in order to shorten the flight distance to deliver ammunition and evacuate wounded soldiers. While medical evacuation was not his mission, he immediately sought volunteers and with complete disregard for his own personal safety, led the two aircraft to Landing Zone X-Ray. Despite the fact that the landing zone was still under relentless enemy fire, Major Crandall landed and proceeded to supervise the loading of seriously wounded soldiers aboard his aircraft. Major Crandall’s voluntary decision to land under the most extreme fire instilled in the other pilots the will and spirit to continue to land their own aircraft, and in the ground forces the realization that they would be resupplied and that friendly wounded would be promptly evacuated. This greatly enhanced morale and the will to fight at a critical time. After his first medical evacuation, Major Crandall continued to fly into and out of the landing zone throughout the day and into the evening. That day he completed a total of 22 flights, most under intense enemy fire, retiring from the battlefield only after all possible service had been rendered to the Infantry battalion. His actions provided critical resupply of ammunition and evacuation of the wounded. Major Crandall’s daring acts of bravery and courage in the face of an overwhelming and determined enemy are in keeping with the highest traditions of the military service and reflect great credit upon himself, his unit, and the United States Army.

Major Bruce Campbell's UH-1D Huey departing LZ X-Ray during the Battle of Ia Drang, 14 November 1965. (U.S. Army)
Major Bruce Campbell’s Bell UH-1D Iroquois, “Ancient Serpent Six,” departing Landing Zone X-Ray during the Battle of Ia Drang, 14 November 1965. (U.S. Army)

© 2016, Bryan R. Swopes

20 October 1956

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Bell XH-40 55-4459 with cowlings and rear doors installed. (U.S. Army)
Bell XH-40 55-4459 with stabilizer bar, cowlings and rear doors installed. (U.S. Army)

20 October 1956: Bell Aircraft Corporation Chief Pilot Floyd W. Carlson and Chief Experimental Test Pilot Elton J. Smith made the first flight of the Bell Model 204 (designated XH-40-BF serial number 55-4459 by the United States Army) at Bell’s helicopter factory in Hurst, Texas.

The XH-40 is a six-place, turboshaft-powered light helicopter, designed with a primary mission of battlefield medical evacuation. Operated by one or two pilots, it could carry four passengers, or two litter patients with an attendant. The prototype’s fuselage was 39 feet, 3.85 inches (12.294 meters) long. The overall length of the helicopter with rotors turning was 53 feet, 4.00 inches (16.256 meters). The height (to the top of the tail rotor arc) is 14 feet, 7.00 inches (4.445 meters). The empty weight of the XH-40 was 3,693 pounds (1,675 kilograms), with a maximum gross weight of 5,650 pounds (2,563 kilograms).

Bell XH-40 first flight. (U.S. Army)
Bell XH-40 first flight. (U.S. Army)

The two blade semi-rigid, under-slung main rotor had a diameter of 44 feet, 0.00 inches (12.294 meters), and turned counter clockwise when viewed from above. (The advancing blade is on the helicopter’s right.) The blades used a symmetrical airfoil. They had a chord of 1 foot, 3.00 inches (0.381 meters) and 10° negative twist. The main rotor hub incorporated pre-coning. At 100% NR, the main rotor turned 324 r.p.m. The two blade tail rotor assembly had a diameter of 8 feet, 6.00 inches (2.591 meters). 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 first prototype Bell XH-40, 55-4459, hovers in ground effect. (U.S. Army)

The prototype XH-40 was powered by a Lycoming LTC1B-1 (XT53-L-1) free-turbine (turboshaft). The engine uses a 5-stage axial-flow, 1-stage centrifugal-flow compressor with a single-stage gas producer turbine and single-stage power turbine. A reverse-flow combustion section with 12 burners allows a significant reduction in the the engine’s total length. The XT53L-1 had a Maximum Continuous Power rating of 770 shaft horsepower, and Military Power rating of 825 shaft horsepower. It could produce 860 shaft horsepower at 21,510 r.p.m. At Military Power, the XT53-L-1 produced 102 pounds of jet thrust (0.454 kilonewtons). The power turbine drives the output shaft through a 3.22:1 gear reduction. The T53-L-1 is 3 feet, 11.8 inches (1.214 meters) long and 1 foot, 11.25 inches (0.591 meters) in diameter, and weighs 460 pounds (209 kilograms).

A Lycoming XT53-L-1 turboshaft engine installed on the first Bell XH-40 prototype, at Hurst, Texas, 10 August 1956. (University of North Texas Libraries, Special Collections)

The XH-40 had a maximum speed of 133 knots (153 miles per hour/246 kilometers per hour) at 2,400 feet (732 meters), and 125 knots (144 miles per hour/232 kilometers per hour) at 5,000 feet (1,524 meters). The in-ground-effect hover ceiling (HIGE) was 17,300 feet (5,273 meters) and the service ceiling was 21,600 feet (6,584 meters). The helicopter’s fuel capacity was 165 gallons (625 liters), giving it a maximum range of 212 miles (341 kilometers).

The Bell XH-40 prototype hovering in ground effect at the Bell Aircraft Company plant at Hurst, Texas. The helicopter's cowlings are not installed in this photograph. (U.S. Army)
The Bell XH-40 prototype hovering in ground effect at the Bell Aircraft Corporation helicopter plant at Hurst, Texas. The helicopter’s cowlings and doors are not installed in this photograph. (U.S. Army)

Three XH-40 prototypes were built, followed by six YH-40 service test aircraft. The designation of the XH-40 was soon changed to XHU-1.

This helicopter was the prototype of what would be known world-wide as the “Huey.” The helicopter was designated by the U.S. Army as HU-1, but a service-wide reorganization of aircraft designations resulted in that being changed to UH-1. Produced for both civil and military customers, it evolved to the Model 205 (UH-1D—UH-1H), the twin-engine Model 212 (UH-1N), the heavy-lift Model 214, and is still in production 66 years later as the twin-engine, four-bladed, glass-cockpit Model 412EPI and the Subaru Bell EPX.

Left rear quarter view of the Bell XH-40 hovering in ground effect at the Bell Helicopter Company plant at Hurst, Texas. (U.S. Army)
Left rear quarter view of the Bell XH-40 hovering in ground effect at the Bell Aircraft Corporation helicopter plant at Hurst, Texas. (U.S. Army)

Sources differ as to the date of the first flight, with some saying 20 October, and at least one saying 26 October, but most cite 22 October 1956. This individual aircraft is at the U.S. Army Aviation Museum, Fort Rucker, Alabama. The museum’s director, Robert S. Maxham, informed TDiA that, “The earliest and only historical record cards that we have on 4459 are dated 2 MAY 1958, and at that time the aircraft had 225.8 hours on it.” The Smithsonian Institution National Air and Space Museum, a generally reliable source, states the first flight was 22 October 1956.

Many sources also state the the XH-40 first flew on the same day on which Lawrence D. Bell died, which was 20 October.

The earliest contemporary news report yet discovered by TDiA, states,

On October 20, after several hours of ground running, the new Bell XH-40 helicopter was flown for the first time.

—FLIGHT and AIRCRAFT ENGINEER, No. 2506, Vol. 71, Friday, 1 February 1957, Page 136, at Column 1

A rare color photograph of of a prototype Bell XH-40, hovering in ground effect. In this photo, a stabilizer bar is installed, and the synchronized elevator has end plates similar to those on Bell Model 47 helicopters. (Unattributed)

Beginning in 2015, XH-40 55-4459 was restored by Blast Off, Inc., at Atmore, Alabama. It was then returned to the Army Aviation Museum.

Bell XH-40 55-4459 ready for transport to Blast Off, Inc., 16 June 2015. (The Atmore Advance)

The Bell XH-40 at the United States Army Aviation Museum.

© 2018, Bryan R. Swopes

6 October 1983

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A flight of two U.S. Army OH-58D Kiowa Warrior scout helicopters. (Bell Helicopter)
A flight of two U.S. Army OH-58D Kiowa Warrior scout helicopters. (Bell Helicopter)

6 October 1983: First flight of the Bell Helicopter Company Model 406/OH-58D Kiowa reconnaissance helicopter. Developed from the earlier Model 206/OH-58A and OH-58C Kiowa, the D model features a four-blade composite main rotor, an upgraded engine and transmission, and improved avionics. The most visible features are the spherical mast-mounted sighting system above the main rotor and much larger engine/transmission cowling, or “dog house.”

The helicopter was designed with very low level, “nap-of-the-Earth,” (NOE) flight, using terrain and trees for cover. The four-bladed rotor provides more lift and increased responsiveness over the two-bladed semi-rigid rotor of the OH-58A and C.

The mast-mounted sight allows the helicopter to hover behind terrain or trees with just the sight exposed. The sight contains television, thermal imaging and laser range-finding and target designation equipment.

The instrument panel of a Bell OH-58D Kiowa. (Bell helicopter)
The instrument panel of a Bell OH-58D Kiowa. (Bell Helicopter)

Operated by two pilots, the Bell OH-58D Kiowa is 42 feet, 2 inches (12.852 meters) long, with rotors turning. The four-bladed composite main rotor has a diameter of 35 feet (10.668 meters). As is customary with American-designed helicopters, the main rotor turn counter-clockwise as seen from above. (The advancing blade is on the right side of the aircraft.) The two-blade semi-rigid tail rotor is mounted on the left side of the tail boom and turns clockwise when seen from the left. (The advancing blade is below the tail boom.) The overall height of the OH-58D is 12 feet, 10–5/8 inches (3.928 meters). Empty weight of the helicopter is about 3,500 pounds (1,588 kilograms), depending on installed equipment. This is approximately 15% greater than the maximum gross weight of the OH-58A. The OH-58D has a maximum gross weight of 5,500 pounds (2,495 kilograms).

Power for the Kiowa is supplied by a Rolls-Royce T703-AD-700A (Allison 250-C30R3) turboshaft engine which produces 750 shaft horsepower. The main transmission is limited to transient input of 637 shaft horsepower.

The helicopter can be armed with a fixed, remotely-fired, M3P .50-caliber (12.7 mm) machine gun, a pod carrying seven 2.75-inch (70 mm) rockets, or two AGM-114 Hellfire antitank guided missiles.

The OH-58D has a cruise speed of 95 knots (109 miles per hour/176 kilometers per hour) when armed. Its range is 140 nautical miles (161 miles/259 kilometers). The hover ceiling in ground effect (HOGE) at +15 °C. is 7,500 feet MSL (2,286 meters).

An OH-58D Kiowa decelerates as it approaches trees at Fort Lewis, Washington.( U.S. Army)
An OH-58D Kiowa decelerates as it approaches trees during gunnery exercises at Fort Lewis, Washington. A .50-caliber machine gun is mounted on the left side of the helicopter. (U.S. Army)

© 2015, Bryan R. Swopes