Tag Archives: Helicopter

9 December 1959

Captain Walter J. Hodgson (1924–1978) and Major William J. Davis, U.S. Air Force, with the world record-setting Kaman H-43B Huskie, 58-1848. (FAI)
Captain Walter J. Hodgson (1924–1978) and Major William J. Davis, U.S. Air Force, with the world record-setting Kaman H-43B Huskie, 58-1848. (FAI)

9 December 1959: At Bloomfield, Connecticut, U.S. Air Force Captain Walter J. Hodgson test pilot and Major William J. Davis flew a Kaman H-43B-KA Huskie, 58-1848, to an altitude of 9,097 meters (29,845.8 feet), setting a Fédération Aéronautique Internationale (FAI) World Record for Altitude Without Payload.¹

Davis and Hodgson were present with the Frederick L. Feinberg Award in 1960, for “demonstrating outstanding skills or achievement,” by the American Helicopter Society.

Anton Flettner, 1885–1961. (Library of Congress)

The Kaman H-43 Huskie was a single-engine helicopter using a unique arrangement of counter-rotating and intermeshing rotors. The two rotors turning in opposite directions counteracted the torque effect, eliminating the need for a anti-torque tail rotor. In helicopters using a tail rotor, as much as 30% of the total engine power is used to drive the tail rotor. By eliminating that requirement, the total engine power could be used to produce lift. The Huskie could lift more weight and climb higher than a similar size helicopter with the same engine.

The Kaman Huskie was designed by German inventor Anton Flettner. He had designed and built the Flettner Fl 282 Kolibri. He was brought to the United States at the end of World War II under Operation Paperclip, and went to work at Kaman Aircraft Corporation, Bloomfield, Connecticut.

The Huskie was used by the U.S. Air Force, U.S. Navy and Marine Corps, primarily for short range rescue operations. It was operated by two pilots and two rescue crewmen.

The fuselage of the H-43 was 25.0 feet (7.62 meters) long. Each rotor had a diameter of 47.0 feet (14.33 meters). The helicopter’s empty weight was 5,900 pounds (2,676 kilograms) and its maximum gross weight was 7,100 pounds (3,221 kilograms).

The H-43B was powered by one Lycoming T53-L-1B turboshaft engine, rated at 860 shaft horsepower at 21,510 r.p.m. 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 allows significant reduction in the the engine’s total length. 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, 11.0 inches (0.584 meters) in diameter. It weighs 460 pounds (209 kilograms).

The Huskie’s maximum speed was 107 miles per hour (172 kilometers per hour). Its hover ceiling in ground effect (HIGE) was 20,000 feet (6,096 meters) and it had a range of 250 miles (402 kilometers).

Kaman H-43B-KA Huskie 58-1848 was reclassified as HH-43B in 1962. It was retired to The Boneyard at Davis-Monthan Air Force Base, Tucson, Arizona, in 1972, and was scrapped in 1977.

Kaman H-43B-KA Huskie 58-1848 at Bloomfield, Connecticut, 9 December 1959. (FAI)
Kaman H-43B-KA Huskie 58-1848 at Bloomfield, Connecticut, 9 December 1959. (FAI)

¹ FAI Record File Number 1869

© 2017, Bryan R. Swopes

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8 December 1945

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. (Bell Helicopter via “Floyd W. Carlson, Helicopter Pioneer”)

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 gear reduction transmission which turned the main rotor through a two-stage planetary gear system. 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. 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

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

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

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10 November 1949

Sikorsky YH-19 49-2012 first flight, Bloomfield, Connecticut, 10 November 1949. (Sikorsky, a Lockheed Martin Company)

10 November 1949: At Bloomfield, Connecticut, Dimitry D. (“Jimmy”) Viner, a nephew of Igor Sikorsky and chief test pilot for the Sikorsky Aircraft Corporation, made the first flight of the prototype Sikorsky S-55 helicopter, serial number 55-001, which the U.S. Air Force had designated YH-19 and assigned serial number 49-2012.

Five YH-19 service test aircraft were built. Two were sent to Korea for evaluation in combat. As a result, the United States Air Force placed an initial order for 50 H-19A Chickasaw helicopters. (It is customary for U.S. Air Force and U.S. Army helicopters to be named after Native American individuals or tribes, though there are exceptions.) This was quickly followed by orders for 264 H-19B helicopters.

Sikorsky YH-19 49-2014 in Korea, circa 1951. (U.S. Air Force)

The United States Navy ordered 118 S-55s which were designated HO4S-1 and HO4S-3. The U.S. Coast Guard bought 30 HO4S-1G and HO4S-3Gs configured for rescue operations. The U.S. Marine Corps purchased 244 HRS-1, HRS-2 and HRS-3 helicopters. The U.S. Army ordered 353 H-19C and H-19D Chickasaw utility transports. The remaining 216 Sikorsky-built helicopters were S-55, S-55C and S-55D commercial models.

Cutaway drawing of the Sikorsky S-55/H-19/HO4S/HRS. Note the rearward-facing, angled placement of the radial engine.(Sikorsky Historical Archives)
Cutaway illustration of the Sikorsky S-55/H-19/HO4S/HRS. Note the rearward-facing, angled placement of the radial engine. (Sikorsky Historical Archives)

The S-55 was flown by two pilots in a cockpit placed above the passenger/cargo compartment. The most significant design feature was moving the engine from directly under the main rotor mast to a position at the front of the helicopter. Installed at an angle, the engine turned a drive shaft to the main transmission. The engine placement provided space for a large passenger/cargo compartment. The aircraft was constructed primarily of aluminum and magnesium, with all-metal main and tail rotor blades.

The main rotor consisted of three fully-articulated blades built of hollow aluminum spars, with aluminum ribs. Spaces within the blade were filled with an aluminum honeycomb. The blades were covered with aluminum sheet. The hollow spars were filled with nitrogen pressurized to 10 p.s.i.  An indicator at the blade root would change color if nitrogen was released, giving pilots and mechanics an indication that the spar had developed a crack or was otherwise compromised. The main rotor turned counter-clockwise as seen from above. (The advancing blade is on the helicopter’s right.) Flapping hinges were offset from the main rotor axis, giving greater control response and effectiveness. The tail rotor was mounted on the helicopter’s left side in a pusher configuration. It turned clockwise as seen from the helicopter’s left.

The helicopter’s fuselage was 42 feet, 2 inches (12.852 meters). The main rotor had a diameter of 53 feet (16.154 meters) and tail rotor diameter was 8 feet, 8 inches (2.642 meters), giving the helicopter an overall length with all blades turning of 62 feet, 2 inches (18.948 meters). It was 13 feet, 4 inches (4.064 meters) high. The landing gear tread was 11 feet (3.353 meters). The S-55 had an empty weight of 4,785 pounds (2,173 kilograms) and maximum takeoff weight of 7,200 pounds (3,271 kilograms). Fuel capacity was 185 gallons (698 liters).

The YH-19 was powered by an air-cooled, supercharged 1,343.804-cubic-inch-displacement (22.021 liter) Pratt & Whitney R-1340-57 (Wasp S1H2) 9-cylinder radial engine mounted at a 35° angle in the fuselage forward of the crew compartment. This was a direct-drive engine which had a Normal Power rating of 550 horsepower at 2,200 r.p.m. to 8,000 feet (2,438 meters), and 600 horsepower at 2,250 r.p.m. for Take Off. Later production S-55 commercial and H-19/HO4S and HRS military helicopters used an air-cooled, supercharged 1,301.868-cubic-inch (21.334 liter) Wright Aeronautical Division 871C7BA1 Cyclone 7 (R-1300-3) 7-cylinder radial engine with a compression ratio of 6.2:1. The R-1300-3 was also a direct-drive engine, but was rated at 700 horsepower at 2,400 r.p.m., Normal Power, and 800 horsepower at 2,600 r.p.m. for Take-Off. Both engines incorporated a large cooling fan to circulate air around the cylinders. The R-1300-3 was 49.68 inches (1.261 meters) long, 50.45 inches (1.281 meters) in diameter, and weighed 1,080 pounds (490 kilograms).

Sikorsky Aircraft Corps. YH-19 49-2012 (c/n 55-001) shown with engine "clam shell" doors open. This allowed excellent access to the engine for maintenance.
Sikorsky Aircraft Corps. YH-19 49-2012 (c/n 55-001) shown with engine “clam shell” doors open. This allowed excellent access to the engine for maintenance. (Sikorsky Historical Archives)

The S-55 had a maximum speed of 95 knots (109 miles per hour, 176 kilometers per hour). The helicopter’s hover ceiling in ground effect (HIGE) was 7,875 feet (2,400 meters) and out of ground effect (HOGE) is 4,430 feet (1,350 meters). The service ceiling was 11,400 feet (3,475 meters) and range was 405 miles (652 kilometers).

Sikorsky Aircraft Corporation built 1,281 S-55-series helicopters. Another 477 were built under license by Westland Aircraft Ltd., Société Nationale des Constructions Aéronautiques du Sud-Est (SNCASE) and Mitsubishi Heavy Industries.

49-1012 is in the collection of the Smithsonian Institution National Air and Space Museum.

The first of five YH-19 service test helicopters, 49-2012 is on display at the Smithsonian Institution National Air and Space Museum. (NASM)
The first of five YH-19 service test helicopters, 49-2012, is on display at the Smithsonian Institution National Air and Space Museum. (NASM)

© 2017, Bryan R. Swopes

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30 October 1991

Sikorsky HH-60G Pave Hawk 88-26118 of the 12th Rescue Wing—a sister ship of Jolly 110—recovers pararescue jumpers during a training mission outside of San Francisco's Golden Gate. (TSGT Lance Cheung, U.S. Air Force)
Sikorsky HH-60G Pave Hawk 88-26118 of the 129th Rescue Wing, California Air National Guard, recovers pararescue jumpers during a training mission outside of San Francisco’s Golden Gate. (Technical Sergeant Lance Cheung, U.S. Air Force)

30 October 1991: United States Air Force Sikorsky HH-60G Pave Hawk, 88-26110, call sign “Jolly 110,” assigned to the 106th Rescue Wing, New York Air National Guard, headed out into a hurricane that would become known as “The Perfect Storm,” to attempt a rescue 250 miles (400 kilometers) out to sea. Aboard were Major C. David Ruvola, pilot; Captain Graham Buschor, co-pilot; Staff Sergeant James R.  Mioli, flight engineer; and pararescue jumpers Technical Sergeant John Spillane and Technical Sergeant Arden Rick Smith.

Due to the severity of the storm (a weather buoy located 264 miles (425 kilometers) south of Halifax, Nova Scotia, reported a wave height of 100.7 feet (30.7 meters) on 30 October—the highest ever recorded in that part of the Atlantic Ocean) the Pave Hawk crew was unable to make the rescue and had to return to their base. Having already refueled from the Lockheed HC-130 Hercules tanker three times during the mission, and with low fuel, a fourth refueling was needed for the helicopter to make it back to the mainland. Because of the the extreme turbulence and lack of visibility, Jolly 110 could not make contact with the refueling drogue trailing behind the airplane. Major Ruvola made more than 30 attempts, but finally both drogues had been damaged by the severe conditions. With just twenty minutes of fuel remaining, Jolly 110 would have to ditch in the middle of “The Perfect Storm.”

Sikorsky HH-60G Pave Hawk 88-26109, sistership of "Jolly 110", ready for refueling from a C-130. (U.S. Air Force)
Sikorsky HH-60G Pave Hawk 88-26109, a sistership of “Jolly 110,” ready for refueling from a Lockheed MC-130P Combat Shadow, 69-5828. This helicopter was destroyed 7 January 2014, when it crashed off the coast of England following multiple bird strikes at 130 knots. The four-man crew was killed. (TSGT Justin D. Pyle, U.S. Air Force)
Technical Sergeant Arden R. Smith, Pararescue Jumper, 106th Rescue Wing, New York Air National Guard. (U.S. Air Force)
Technical Sergeant Arden R. Smith, Pararescue Jumper, 106th Rescue Wing, New York Air National Guard. (U.S. Air Force)

Unable to refuel, Major Ruvola made the decision to ditch the helicopter into the sea while the engines were still running. Finally, at 9:30 p.m., the number one engine flamed out from fuel starvation. Ruvola held the Pave Hawk in a hover over the raging ocean while Buschor, Mioli, Spillane and Smith jumped.

When the number two engine flamed out, Ruvola put the Pave Hawk into a hovering autorotation, its blades coming to a sudden stop when they hit the face of an oncoming wave. Ruvola was about 15 feet (4.6 meters) under water by the time he was able to escape from the sinking helicopter.

The Pave Hawk had gone down 90 miles (145 kilometers) south of Montauk Point in 100-knot (185 kilometers per hour) winds and 80-foot (25 meter) waves. After five hours in the water, four airmen were rescued by USCGC Tamaroa (WMEC-166), a 48-year-old former U.S. Navy fleet tug, operated by the Coast Guard since the end of World War II as a medium endurance cutter.

The search for Rick Smith continued for a week. He was never found.

USCGC Tamaroa (WMEC-166). (U.S. Coast Guard)
USCGC Tamaroa (WMEC-166). (U.S. Coast Guard)
USCGC Tamaroa (WHEC-166) pitches and rolls in heavy seas during the rescue of Satori, during "The Perfect Storm". (U.S. Coast Guard)
USCGC Tamaroa (WMEC-166) pitches and rolls in heavy seas during the rescue of Satori, 29 October 1991. (U.S. Coast Guard) 

The U.S. Air Force HH-60G Pave Hawk is medium-sized twin-engine combat search-and-rescue (CSAR) helicopter, developed from the Army UH-60A Black Hawk transport. These helicopters were upgraded with an extendable probe for air-to-air refueling and additional fuel tanks in the cabin and given the project name Credible Hawk. They were further upgraded to the MH-60G Pave Hawk standard which incorporated a system of inertial navigation, GPS and Doppler radar for precision navigation. Low-light television, infrared cameras and night vision systems allowed the MH-60G to operate at night and very low altitude. The Pave Hawk is equipped with an Automatic Flight Control System (AFCS), a very sophisticated autopilot which incorporates automatic hover capability. Some of the MH-60G Pave Hawks received further upgrades for the special operations mission. Helicopters dedicated to CSAR were redesignated HH-60G. A rescue hoist capable of lifting 600 pounds (272 kilograms) from a 200-foot (60.7 meter) hover is incorporated on the upper right side of the fuselage.

Sikorsky HH-60G Pave Hawk, 88-26107, sister ship of 88-26110, which was lost in "The Perfect Storm".
Sikorsky HH-60G Pave Hawk, 88-26107, sister ship of 88-26110, which was lost in “The Perfect Storm.” (U.S. Air Force)

The HH-60G is operated by a crew of two pilots, a flight engineer and gunner. For rescue operations, pararescue jumpers, the famous “P.J.s,” are added to the crew. The helicopter has an overall length of 64 feet, 11 inches (19.787 meters) with rotors turning. The fuselage is 49 feet, 10 inches (15.189 meters) long and 7 feet, 9 inches (2.362 meters) wide. Overall height (rotors turning) is 16 feet, 11 inches (5.156 meters).

The fully-articulated main rotor has a diameter of  53 feet, 8 inches (16.358 meters) and turns counterclockwise as seen from above. (The advancing blade is on the helicopter’s right.) The main rotor turns 258 r.p.m., resulting in a blade tip speed of 725 feet per second (221 meters per second). The four blades have a chord of 1.73 feet (0.527 meters) and 18° negative twist. The blade tips are swept back at a 20° angle. The four-blade tail rotor assembly is mounted on the right side of a pylon in a tractor configuration. The tail rotor plane is inclined 20° to the left to provide approximately 400 pounds of additional lift. The tail rotor turns clockwise as seen from the helicopter’s left side. (The advancing blade is below the axis of rotation.) The tail rotor has a diameter of 11 feet (3.353 meters) and each blade has a chord of 0.81 feet (0.247 meters). The tail rotor has a tip speed of 699 feet per second (213 meters per second).

Sikorsky HH-60G Pave Hawk 88-26106, sister ship of Jolly 110, at William J. Fox Field, Lancaster, California. (Alan Radecki)
Sikorsky HH-60G Pave Hawk 88-26106 at William J. Fox Field, Lancaster, California. (Alan Radecki)

Power is supplied by two General Electric T700-GE-701C turboshaft engines which are mounted on top of the fuselage on either side of the transmission and main rotor mast. They have a Maximum Continuous Power rating of 1,662 shaft horsepower, each, at Sea Level on a Standard Day. Maximum Power (10 minute limit) is 1,890 shaft horsepower, and the One Engine Inoperative (OEI) rating is 1,940 shaft horsepower (2½ minute limit.) The -701C is 3 feet, 10 inches (1.684 meters) long), 1 foot,3.6 inches (0.396 meters) in diameter and weighs 458 pounds (208 kilograms). The helicopter’s main transmission is rated for a maximum 3,400 horsepower.

Sikorsky HH-60G Pave Hawk 91-26403, 33rd Rescue Squadron, Kadena Air Base, Japan, 2001. (MSgt Val Gempis, United States Air Force)

The HH-60G has a cruise speed of 184 miles per hour (296 kilometers per hour) and its maximum speed is 224 miles per hour (361 kilometers per hour). The service ceiling is 14,000 feet (4,267 meters) and maximum range is 373 miles (600 kilometers). The hover ceiling, in ground effect (HIGE) is approximately 10,000 feet (3,048 meters), and out of ground effect (HOGE) is about 6,000 feet (1,830 meters).

Defensive armament consists of two GAU-18A .50-caliber machine guns.

The U.S. Air Force initially purchased 112 HH-60G Pave Hawk helicopters, though as of May 2016, 96 remain in service. Most of these are approaching their design airframe lifetime limit of 7,000 flight hours and several have surpassed that by as much as 3,000 hours. There are plans to replace them with a new HH-60W, a combat rescue helicopter based on the Sikorsky UH-60M Black Hawk. Currently, 21 U.S. Army UH-60Ls are being modified to replace HH-60G losses. The next version, the HH-60W, based on the Sikorsky UH-60M, is expected to enter the U.S. Air Force inventory by March 2020.

Sikorsky HH-60G Pave Hawk 89-26212. (U.S. Air Force)
Captain Marisa Catlin, 83rd Expeditionary Rescue Squadron, flies a Sikorsky HH-60G Pave Hawk, 89-26212, over the Kunar Province, Afghanistan, 9 February 2011. (Captain Erick Saks, U.S. Air Force)

© 2017, Bryan R. Swopes

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