Tag Archives: Prototype

21 November 1947

Corky Meyer in the cockpit of the first Grumman XF9F-2 Panther, Bu. No. 122475, during the first flight, 21 November 1947. (U.S. Navy)
Corky Meyer in the cockpit of the first Grumman XF9F-2 Panther, Bu. No. 122475, during the first flight, 21 November 1947. (Grumman Aircraft Engineering Corporation)
Corwin H. ("Corky") Meyer
Corwin Henry Meyer, 1920–2011. (Grumman)

21 November 1947: Grumman Aircraft Engineering Corporation engineering test pilot Corwin Henry (“Corky”) Meyer took off from the company’s 5,000 foot runaway at Bethpage, Long Island, New York, in the first prototype XF9F-2 Panther, Bu. No. 122475. After the preliminary flight evaluation, Meyer landed the new jet fighter on a longer runway at Idlewild Airport. The Bethpage runway was only 5,000 feet (1,524 meters) long. As the first jet aircraft built by Grumman, it wasn’t known if the XF9F-2 could land on that short a runway.

Air & Space/Smithsonian magazine quoted Meyer as saying that the weather was “the foulest of any first flight in my experience.” He described the prototype’s handling qualities: “It handled like a J-3 Cub.” In an article for Flight Journal, Corky Meyer wrote: “I conducted a very satisfactory first flight of the 5,000-pound-thrust Rolls-Royce Nene-powered fighter on November 21, 1947.”

Corwin H. Meyer also made the first flights in Grumman’s F7F Tigercat, F8F Bearcat, F9F Panther and Cougar, and F11F Tiger. He eventually rose to Senior Vice President of Grumman Aerospace Corporation.

Grumman XF9F-2 prototype, photographed 20 November 1947. (Grumman Aircraft Engineering Corporation)

The XF9F-2 Panther was the first jet-powered aircraft to be built by Grumman, a major supplier of aircraft for the United States Navy. It was a single-seat, single-engine, day fighter, designed for operation on the U.S. Navy’s aircraft carriers. It was developed from a proposed four-engine XF9F-1 night fighter. Grumman planned to use the Rolls-Royce RB.41 Nene centrifugal-flow turbojet engine. With 5,000 pounds rated thrust at 12,400 r.p.m., the Nene was more powerful (and more reliable) than any engine manufactured by an American company.

The first prototype Grumman XF9F-2 Panther at Grumman's Plant 4, 1947. (Grumman Aircraft Engineering Corporation)
The first prototype Grumman XF9F-2 Panther at Grumman’s Plant 4, 1947. (Grumman Aircraft Engineering Corporation)

Originally it was planned that the Nene would be licensed for production to the Taylor Turbine Corporation as the J42-TT-2. No J42s were ready, so Taylor supplied Grumman with imported Rolls-Royce engines. The Navy had concerns about Taylor’s capability to produce engine in sufficient quantities and arranged for the J42 license to be sold to Pratt & Whitney.

Ensign Neil A. Armstrong, as wingman to Lieutenant (j.g.) Ernie Moore, is flying the second Grumman F9F-2 Panther, Bu. No. 125122 (marked S 116), assigned to VF-51, USS Essex (CV-9), 1951. (Naval Aviation Museum)
Ensign Neil A. Armstrong, as wingman to Lieutenant (j.g.) George Russell, is flying the second Grumman F9F-2 Panther, Bu. No. 125122 (marked S 116), assigned to VF-51, USS Essex (CV-9), 1951. (John Moore/Naval Museum of Naval Aviation)

The Panther was placed into production as the F9F-2. The F9F-2 was 37 feet, 5-3/8 inches (11.414 meters) long with a wingspan of 38 feet, 5⅜ inches (11.719 meters) long, with a wingspan of 38 feet, 0 inches (11.528 meters)— not including wing tanks. Its overall height was 11 feet, 4 inches (3.454 meters). The wings could be hydraulically folded to reduce the span for storage aboard ship. The Panther weighed 9,303 pounds (4,220 kilograms) empty, and had a gross weight of 19,494 pounds (8,842 kilograms.

Grumman F9F-5 Panther, Bu. No. 126034, of VF-781, catches an arresting cable when landing aboard USS Oriskany (CVA-34), 1952. (U.S. Navy)
Grumman F9F-5 Panther, Bu. No. 126034, of VF-781, catches an arresting cable when landing aboard USS Oriskany (CVA-34), 15 November 1952. (U.S. Navy)

The F9F-2 was powered by a Pratt & Whitney JT6 (J42-P-8) turbojet engine which produced 5,000 pounds of thrust (22.241 kilonewtons) at Sea Level, and 5,750 pounds (25.577 kilonewtons) with afterburner. The J42 was a license-built version of the Rolls-Royce Nene. The engine used a single-stage centrifugal-flow compressor, 9 combustion chambers and a single-stage axial-flow turbine. The J42-P-8 weighed 1,715 pounds (778 kilograms).

The Panther had a maximum speed of 575 miles per hour (925 kilometers per hour) at Sea Level. Its service ceiling was 44,600 feet (13,594 meters), and the range was 1,353 miles (2,177 kilometers).

The Panther was armed with four M3 20 mm autocannon placed in the nose. It could carry up to 3,000 pounds (1,361 kilograms) of bombs or eight 5-inch (12.7 centimeters) rockets on four hardpoints under each wing.

Lt. Royce Williams, USN, points out battle damage to his Grumman F9F-5 Panther, aboard USS Oriskany (CVA-34), 18 November 1952. (U.S. Navy)
Lt. Royce Williams, USN, points out battle damage to his Grumman F9F-5 Panther, Bu. No. 125459, aboard USS Oriskany (CVA-34), 18 November 1952. (U.S. Navy via Flight Journal)

It was a very successful air-to-air and air-to-ground fighter during the Korean War. On 18 November 1952, Lieutenant Elmer Royce Williams, USN, flying an F9F-5 Panther, Bu. No. 125459, of VF-781 aboard the aircraft carrier USS Oriskany (CVA-34), shot down four of seven Soviet Air Force MiG 15 fighters which had launched from Vladivostok toward Task Force 77. His Panther sustained significant damage from enemy cannon shells. Though he safely returned to his carrier, the fighter, Number 106, was so badly damaged that it was pushed over the side. Lieutenant Royce was awarded the Silver Star for this action. No other pilot has ever shot down four MiG fighters during a single combat action.

This Grumman F9F-5 Panther aboard the USS Midway Museum, San Diego, California, is painted to represent Royce Williams' fighter. (USS Midway Museum)
This Grumman F9F-5 Panther aboard the USS Midway Museum, San Diego, California, is painted to represent Royce Williams’ fighter. (USS Midway Museum)

The F9F Panther was flown during the Korean War by such famed naval aviators as Ted Williams, and future astronauts John Glenn and Neil Armstrong.

Grumman built 1,358 F9F-2,-3,-4 and -5 Panthers and another 1,392 swept wing F9F-6, -7 and -8 Cougars. Panthers remained in service with the United States Navy until 1958, and Cougars until 1974.

The combat survivability of Grumman's fighters earne dteh factory the nickname of "The Grumman Iron Works". In this photograph, future NASA astronaut John H. Glenn, the first American to orbit the Earth, examines some of the 714 holes in his F9F Panther. (U.S. Navy)
The combat survivability of Grumman’s fighters earned the factory the nickname of “The Grumman Iron Works”. In this photograph, future NASA astronaut Major John H. Glenn, U.S. Marine Corps, the first American to orbit the Earth, examines some of the 714 holes in his F9F Panther. (U.S. Navy)

© 2016, Bryan R. Swopes

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20 November 1940

North American Aviation's NA-73X fighter prototype, engine idling, with Vance Breese in the cockpit at Mines Field, Los Angeles, 26 October 1941. (North American Aviation Inc.)
North American Aviation’s NA-73X fighter prototype, engine idling, with Vance Breese in the cockpit at Mines Field, Los Angeles, 26 October 1940. (North American Aviation Inc.)

20 November 1940: North American Aviation’s Chief Test Pilot, Paul Baird Balfour, made his first flight in the NA-73X, NX19998, prototype for a Royal Air Force fighter, the Mustang Mk.I.

Vance Breese was the free-lance test pilot who made the first seven flights in the new airplane. Breese claimed to have made a bet with North American executives that Balfour would crash the prototype on his first flight.

Paul B. Balfour (1908–1951). This is Balfour’s NAA employee file card. (North American Aviation Inc.)

This flight was scheduled to be a high speed test. Edgar Schmued, the designer, offered to show Balfour around the airplane. “Before this flight, I asked Balfour to get into the airplane and go through the routine of a takeoff and flight. He responded that one airplane is like another and he would not need the routine checkout.”

The ground crew started the NA-73X’s 1,150 horsepower Allison V-1710-39 liquid-cooled V-12 engine at 5:40 a.m. and let it warm up to normal operating temperature. When it was restarted just prior to Paul Balfour’s flight, “it was a little hard to start,” according to Olaf Anderson, the airplane’s mechanic.

The prototype Mustang, NA-73X, lies upside down in a plowed field, 20 November 1941. (North American Aviation Inc.)
The prototype Mustang, NA-73X, lies upside down in a plowed field, 20 November 1940. (North American Aviation Inc.)

Balfour took off from Mines Field at about 7:10 a.m. After about twelve minutes of flight, the Allison stopped running. Balfour was too far from Mines Field to make it back to the runway. He landed in a plowed field west of Lincoln Boulevard. When the tires hit the soft surface, the prototype flipped over. Balfour was not hurt and was able to crawl out of the upside-down wreck.

The Civil Aeronautics Board report described the damage as “engine housing broken, both wingtips damaged, tail surfaces damaged, top of fuselage damaged, and other miscellaneous damage.” The NA-73X had accumulated just 3 hours, 20 minutes of flight.

Vance Breese won his bet.

Paul Balfour was not injured in the crash landing, but the NA-73X prototype was significantly damaged. (North American Aviation Inc.)
Paul Balfour was not injured in the crash landing, but the NA-73X prototype was significantly damaged. (North American Aviation Inc.)

According to the C.A.B. investigation, the engine had stopped due to fuel starvation when Balfour neglected to select another tank.

The prototype was taken back to the factory and rebuilt. It would become the famous Mustang, one of the most significant aircraft of World War II.

Damage to the wingtips, tail surfaces, fuselage. (North American Aviation Inc.)
Damage to the wingtips, tail surfaces, fuselage. (North American Aviation Inc.)

Robert C. Chilton was hired as the new Chief Test Pilot. He would continue testing the Mustang developments throughout the war. Chilton made his first flight in NA-73X on 3 April 1941.

The Mustang prototype was hoisted out of the plowed field and taken back to the factory where it was rebuilt. (North American Aviation Inc.)
The Mustang prototype was hoisted out of the plowed field and taken back to the factory where it was rebuilt. (North American Aviation Inc.)

Paul Balfour continued to work for North American Aviation, testing the NA-40 and NA-40B prototypes and the B-25 Mitchell medium bomber. He later served in the United States Air Force.

Paul Baird Balfour was born 5 July 1908 in Washington State. He was the son of Fred Patrick Balfour and Edna May Baird Balfour. Balfour attended two years of college.

Paul Balfour entered the U.S. Army Air Corps (prior to 1930). He was stationed at Rockwell Field, San Diego, California.

Balfour married Martha Lillette Cushman of Coronado, California, at Yuma, Arizona, 6 June 1930.

Balfour began working as a test pilot for North American Aviation, Inc., 1 March 1936.

On 2 July 1938, he married Lois Tresa Watchman at Kingman, Arizona. They would have two children.

Paul B. Balfour, center, with a North American Aviation B-25 Mitchell medium bomber. (Photograph courtesy of Neil Corbett, Test and Research Pilots, Flight Test Engineers)
Paul B. Balfour, center, with a North American Aviation B-25 Mitchell medium bomber. (Photograph courtesy of Neil Corbett, Test and Research Pilots, Flight Test Engineers)

On 9 November 1951, Major Paul B. Balfour, U.S. Air Force, attached to the 1002nd Inspector General Group at Norton Air Force Base, California, was flying a North American VB-25J, 44-30955, a transport conversion of a B-25J-30-NC Mitchell medium bomber.

Shortly after takeoff, at about 10:00 a.m., the airplane developed engine trouble. Unable to return to Norton, Balfour attempted a belly landing at a small private airfield. Witness saw that the airplane’s left engine was idling, and its propeller was feathered. As he approached, the airplane was blocked by a windbreak of eucalyptus trees bordering U.S. Route 66. Balfour banked away from the trees but the B-25 crashed in an orange grove along Bloomington Avenue in Rialto, approximately 7 miles (11 kilometers) north of Norton.

Balfour, still buckled in his seat, was thrown clear of the burning wreck and landed in the street. One man on board was killed and two others seriously injured. Balfour died in a hospital three hours later. He was 41 years old. Major Balfour was buried at the Inglewood Park Cemetery, Inglewood, California.

Burning wing of North American VB-25J 44-30955, near Rialto, California, 9 November 1951.
Burning wing of North American VB-25J 44-30955, near Rialto, California, 9 November 1951.

© 2016, Bryan R. Swopes

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18 November 1930

Boeing XP-9
Boeing XP-9 prototype A.C. 28-386, photographed 14 August 1930. (San Diego Air and Space Museum Archives)

18 November 1930: The prototype Boeing XP-9, Air Corps serial number A.C. 28-346, a single-seat, single-engine monoplane pursuit, made its first flight at Wright Field, Ohio.

This was Boeing’s first semi-monocoque aircraft, built of a sheet dural skin over metal formers. The Army Air Corps issued the contract 29 April 1928 and the aircraft was completed in September 1930, then shipped by railroad to the Army test base.

The XP-9 (Boeing Model 96) was a single-place, single-engine high-wing monoplane with fixed landing gear. It was 25 feet, 1.75 inches (7.665 meters) long. with a wingspan of 36 feet, 6 inches (11.125 meters) and height of 7 feet, 10.25 inches ( meters). The prototype’s empty weight was 2,669 pounds (1,211 kilograms) and its maximum takeoff weight was 3,623 pounds (1,643 kilograms).

The pursuit prototype was powered by a pressurized-liquid-cooled, supercharged, 1,570.381-cubic-inch-displacement (25.734 liter) Curtiss Super Conqueror SV-1570-C dual-overhead camshaft (DOHC) 60° V-12 engine with 4 valves per cylinder. This engine was rated at 600 horsepower at 2,400 r.p.m. It weighed 920 pounds (417 kilograms)

The airplane had a maximum speed of 213 miles per hour (343 kilometers per hour). The service ceiling was 26,800 feet (8,169 meters). Armament was a combination of two machine guns, either one .30-caliber and one .50-caliber, or two .50 caliber, mounted one each side of the fuselage, firing forward.

The placement of the single high wing seriously restricted the pilot’s vision, making landings very dangerous. The airplane was highly unstable in flight. Increasing the size of the tail surfaces did little to improve this. After just 15 flight hours, the XP-9 was permanently grounded and was used as an instructional airframe.

The performance and handling of the XP-9 was considered to be so poor that an option to buy five pre-production models was canceled.

The XP-9’s sole redeeming quality was its method of construction, which has been almost universal since that time.

Boeing XP-9 3/4 front view. (U.S. Air Force photo)
Boeing XP-9 A.C. 28-386. (NMUSAF)

© 2016, Bryan R. Swopes

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16 November 1970

Lockheed L-1011 Tristar, N1011. (Lockheed)
Lockheed L-1011 Tristar, N1011. (Lockheed Martin)

16 November 1970: At the Lockheed California Company Plant 10, just north of Palmdale in the high desert of Southern California, test pilot Henry Baird (“Hank”) Dees, co-pilot Ralph C. Cokely (formerly a Boeing 747 test pilot), with flight test engineers Glenn E. Fisher and Rod Bray, took the new prototype Lockheed L-1011-1 TriStar, N1011, on its first flight.

During the 2½-hour test flight, the airliner reached 250 knots (288 miles per hour, 463 kilometers per hour) and 20,000 feet (6,096 meters).

The prototype Lockheed L-1011 Tristar parked inside the production hangar at Plant 10, Palmdale, California. (Lockheed)
The prototype Lockheed L-1011 TriStar parked inside the production hangar at Plant 10, Palmdale, California. (Lockheed Martin)

The Lockheed L-1011 TriStar is a three-engine wide body airliner designed to carry up to 400 passengers on medium or long distance routes. It is operated by a flight crew of three. The prototype, the L-1011-1 and L-1011-200 production aircraft were 177 feet, 8½ inches (54.166 meters) long with a wingspan of 155 feet, 4 inches (47.346 meters). The longer range, higher gross weight L-1011-500 variant was 164 feet, 2½ inches (50.051 meters) long with a wingspan of 164 feet, 4 inches (50.089 meters). All TriStars have an overall height of 55 feet, 4 inches (16.866 meters). The interior cabin width is 18 feet, 11 inches (5.766 meters). Empty weight ranges from 241,700 pounds (109,633 kilograms) to 245,400 pounds (111,312 kilograms), while the maximum takeoff weight varies from 430,000 pounds (195,045 kilograms) to 510,000 pounds (231,332 kilograms).

N1011, the prototype Lockheed L-10ll TriStar, taxis to the ramp at Plant 10, at Palmdale, California, 16 November 1970. (Photograph © Jon Proctor, used with permission)
N1011, the prototype Lockheed L-10ll TriStar, taxis to the ramp at Plant 10, at Palmdale, California, 16 November 1970. (Photograph © Jon Proctor, used with permission)

The L-1011-1 aircraft were powered by three Rolls Royce RB.211-22B-02 high bypass turbofan engines, producing 42,000 pounds of thrust (186.825 kilonewtons). The -200 and -500 variants used the more powerful RB.211-524B4 which produces 53,000 pounds (235.756 kilonewtons). The RB.211-22 is a “triple-spool” axial-flow turbine engine. It has a single fan stage, 13-stage compressor (7 intermediate- and 6 high-pressure stages), single combustion chamber, and 5 stage turbine section (1 high-, 1 intermediate- and three low-pressure stages). The -22B is 10 feet, 11.4 inches (3.033 meters) long and its fan diameter is 7 feet, 0.8 inches (2.154 meters). It weighs 9,195 pounds (4,171 kilograms).

Lockheed L-1011 TriStar N1011. (Jon Proctor via Wikipedia)
Lockheed L-1011 TriStar N1011 parked on the ramp at Plant 10, Palmdale, California, 16 November 1970. (Jon Proctor via Wikipedia)

Depending on the model, the L-1011 series had a cruise speed of 520–525 knots (598–604 miles per hour, 963–972 kilometers per hour) and a maximum speed of 0.95 Mach. The service ceiling was 42,000–43,000 feet (12,802–13,106 meters). Maximum range for the long range -500 was 6,090 nautical miles (7,008 miles, 11,279 kilometers).

The Lockheed L-1011 TriStar was a very technologically advanced airliner for the time. It was the first to be certified for Category IIIc autolanding, in which the airplane’s automatic flight system could land the airplane in “zero-zero” weather conditions.

Lockheed built 250 L-1011s between 1970 and 1984. Sales were delayed because of problems with delivery of the Rolls-Royce turbofans, giving an early advantage to the competitor McDonnell DC-10, of which 446 were built.

Few TriStars remain in service. The prototype, N1011, was scrapped at Ardmore, Oklahoma, in August 1996. A portion of its fuselage, painted in Delta Air Lines livery, is on display at Atlanta-Hartsfield International Airport, Atlanta, Georgia.

Lockheed L-1011 protoype during Mimum Unstick Speed (Vmu) speed test. (Lockheed Martin)
Lockheed L-1011 prototype during Minimum Unstick (Vmu) speed test for FAA certification. (Lockheed Martin)

© 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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