Tag Archives: Pratt & Whitney Wasp Jr. T1B4

1 October 1947

October 1, 2024AviationAir Mail, Helicopter, Los Angeles Airways, Pratt & Whitney R-985 AN-5, Pratt & Whitney Wasp Jr. T1B4, Sikorsky Aircraft Corporation, Sikorsky S-51, Terminal Annex Post OfficeBryan Swopes

1 October 1947: Los Angeles Airways began regularly scheduled air mail service in Los Angeles, using the Sikorsky S-51 helicopter.

“. . . the U.S. Civil Aeronautics Board awarded LAA the route authorities to operate local air mail services in Southern California using the Sikorsky S-51. Before long, LAA was operating a twice-a-day mail service between the main downtown post office and Los Angeles International Airport along with a small package air express service.

“With a fleet of five S-51s, LAA’s first year of operations resulted in 700 tons of mail being carried with approximately 40,000 landings throughout the Los Angeles metropolitan area. The small operation maintained a 95% reliability rate and by the time it began its small package air express service in 1953, it was annually moving nearly 4,000 tons of mail a year.

“In July 1951 the CAB awarded LAA’s reliable helicopter operation the rights for passenger services which started in November 1954 with larger Sikorsky S-55 helicopters while the smaller S-51s continued the mail and small package services. . . .”

— Tails Through Time, http://aviationtrivia.blogspot.com/2010/06/on-1-october-1947-los-angeles-airways.html

The S-51 was a commercial version of the Sikorsky R-5 series of military helicopters. It was a four-place, single-engine helicopter, operated by one pilot. The cabin was built of aluminum with Plexiglas windows. The fuselage was built of plastic-impregnated plywood, and the tail boom was wood monocoque construction. The main rotor consisted of three fully-articulated blades built of metal spars and plywood ribs and covered with two layers of fabric. (All metal blades soon became available.) The three bladed semi-articulated tail rotor was built of laminated wood. The main rotor turned counter-clockwise, as seen from above. (The advancing blade is on the helicopter’s right.) 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 41 feet, 7.5 inches (12.687 meters) long. The main rotor had a diameter of 48 feet (14.630 meters) and tail rotor diameter was 8 feet, 5 inches (2.565 meters), giving the helicopter an overall length of 57 feet, 1 inch (17.399 meters). It was 13 feet, 1.5 inches (4.001 meters) high. The landing gear tread was 12 feet (3.7 meters). The S-51 had an empty weight of 4,050 pounds (1,837 kilograms) and maximum takeoff weight of 5,500 pounds (2,495 kilograms). Fuel capacity was 100 gallons (378.5 liters).

The helicopter was powered by an air-cooled, supercharged, 986.749-cubic-inch-displacement (16.170 liter) Pratt & Whitney Wasp Jr. T1B4 (R-985 AN-5) direct-drive, nine-cylinder radial engine which was placed vertically in the fuselage behind the crew compartment. This engine was rated at 450 horsepower at 2,300 r.p.m., Standard Day at Sea Level. The R-985 AN-5 was 48.00 inches (1.219 meters) long, 46.25 inches (1.175 meters) in diameter and weighed 684 pounds (310.3 kilograms) with a magnesium crankcase.

The S-51 had a maximum speed (Vne) of 107 knots (123.1 miles per hour/198.2 kilometers per hour). Range was 275 miles (442.6 kilometers). The service ceiling was 14,800 feet (4,511 meters). The absolute hover ceiling was 3,000 feet (914.4 meters).

Of 220 helicopters in the S-51 series built by Sikorsky, 55 were commercial models.

Los Angeles Airways Sikorsky S-51 (Viewliner) — A Los Angeles Airways Sikorsky S-51. The main rotor hub is covered. (Viewliner)

18 August 1943

August 18, 2024Aviation43-28236, c/n 33, Charles Lester Morris, Dimitry D. Viner, First Flight, Jackson E. Beighle, Les Morris, Pratt & Whitney R-985 AN-5, Pratt & Whitney Wasp Jr. T1B4, Sikorsky S-48, Vought-Sikorsky Aircraft Division, Vought-Sikorsky VS-327, Vought-Sikorsky XR-5Bryan Swopes

The second Sikorsky XR-5, 43-28237 (c/n 34). (Sikorsky, a Lockheed Martin Company)

18 August 1943: At Bridgeport, Connecticut, Sikorsky chief test pilot Charles Lester (“Les”) Morris made the first flight of the Vought-Sikorsky VS-327, c/n 33. Also known as the Sikorsky Model S-48, the U.S. Army Air Corps designated the helicopter XR-5 and assigned the serial number 43-28236.

The XR-5 was a significant improvement over the earlier R-4. Its narrow fuselage was streamlined and the cockpit had excellent visibility. The R-4’s box-like fuselage interfered with the downward flow of air from the main rotor, and this was a consideration in the shape of the new helicopter.

The Sikorsky XR-5 (Model S-48) was a single-engine, two-place helicopter. The cabin was built of aluminum with plexiglas windows. The fuselage was built of plastic-impregnated plywood and the tail boom was wood monocoque construction. The main rotor consisted of three fully-articulated blades built of wood spars and ribs and covered with fabric. The three bladed semi-articulated tail rotor was built of laminated wood. The main rotor turned counter-clockwise as seen from above. (The advancing blade is on the helicopter’s right.) 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.

There were five XR-5 helicopters, followed by twenty-six YR-5A service test helicopters built between November 1944 and July 1945. There were slight changes from the earlier five XR-5A prototypes. The R-5A went into production in July 1945 and more than 300 had been built by the time production ended in 1951.

The helicopter’s fuselage was 41 feet, 7½ inches (12.687 meters) long. The main rotor had a diameter of 48 feet (14.630 meters) and tail rotor diameter was 8 feet, 5 inches (2.2.565 meters), giving the helicopter an overall length of 57 feet, 1 inch (17.399 meters) with rotors turning. It was 13 feet, 1½ inches (4.001 meters) high. The landing gear tread was 12 feet (3.7 meters). The R-5A had an empty weight of 3,780 pounds (1,714.6 kilograms) and maximum takeoff weight of 4,900 pounds (2,222.6 kilograms). Fuel capacity was 100 gallons (378.5 liters).

Chief Test Pilot Les Morris with Captain Jackson E. Beighle, U.S. Army Air Corps, hovers a Sikorsky YR-5A, 43-46603, at Bridgeport, with ten additional passengers, 29 November 1945. (Sikorsky, a Lockheed Martin Company)

The R-5 had a maximum speed (Vne) of 107 knots (123.1 miles per hour/198.2 kilometers per hour). Range was 275 miles (442.6 kilometers). The service ceiling was 14,800 feet (4,511 meters). The absolute hover ceiling was 3,000 feet (914.4 meters).

On 13 September 1943, Dimitry D. (“Jimmy”) Viner was hovering out of ground effect at 75 feet (23 meters) when 43-28236 suffered a tail rotor failure. The helicopter made a hard landing and was dignificantly damaged. Neither Viner nor his passenger were injured.

In 1944, while flying to a war bond rally in Nebraska, XR-5 43-28236 suffered an engine failure and crash landed. The helicopter was damaged beyond repair and was stripped for parts.

Thanks to regular This Day in Aviation reader Mike for suggesting this subject.

Igor Sikorsky in the cockpit of a production R-5 helicopter. (Sikorsky, a Lockheed Martin Company)

4 August 1950

August 4, 2024Aviation3rd Air Rescue Squadron, 3rd ARS, 3rd Emergency Rescue Squadron, Air Rescue Service, Claude C. Crest Jr., H-5, Helicopter, HO3S, Hoverfly, Korean War, Medical Evacuation, Pratt & Whitney R-985 AN-5, Pratt & Whitney Wasp Jr. T1B4, Sikorsky, Sikorsky H-5F, Sikorsky R-5F, Sikorsky S-51Bryan Swopes

Sikorsky R-5 medevac, Korean War — A U.S. Air Force Sikorsky H-5F lifts off during the Korean War. (U.S. Air Force)

4 August 1950: During the Battle of the Pusan Perimeter, wounded soldiers were evacuated from the battlefield by helicopter for the first time when a Sikorsky H-5F of Detachment F, 3rd Emergency Rescue Squadron,¹ Air Rescue Service, United States Air Force, flew Private 1st Class Claude C. Crest, Jr., U.S. Army, from the Sengdang-ni area to an Army hospital. By the end of combat in 1953, 21,212 soldiers had been medevaced by helicopters.

Only the second military helicopter, the H-5 was frequently flown overloaded and outside of its center of gravity limits. The helicopter was not armed, though the pilot normally carried an M1911 .45-caliber semi-automatic pistol, and the crewman, a .30-caliber M1 Carbine.

Eleven commercial Sikorsky S-51 helicopters had been purchased by the Air Force in 1947 and designated R-5F. This was later changed to H-5F. It was a four-place, single-engine helicopter, operated by one pilot. The cabin was built of aluminum with Plexiglas windows. The fuselage was built of plastic-impregnated plywood, and the tail boom was wood monocoque construction. The main rotor consisted of three fully-articulated blades built of metal spars and plywood ribs, covered with two layers of fabric. (All metal blades soon became available.) The three bladed semi-articulated tail rotor was built of laminated wood. The main rotor turned counter-clockwise, as seen from above. (The advancing blade is on the helicopter’s right.) Its normal operating range was 175–195 r.p.m. 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 advancing blade is below the axis of rotation.)

Sikorsky S-51 three-view drawing with dimensions. (Sikorsky Historical Archives)

The helicopter’s fuselage was 41 feet, 1¾ inches (12.541 meters) long. The main rotor had a diameter of 48 feet, 0 inches (14.630 meters) and the tail rotor diameter was 8 feet, 5 inches (2.565 meters),² giving the helicopter an overall length of 57 feet, ½ inch (17.386 meters) with rotors turning. It was 12 feet, 11–3/8 inches (3.947 meters) high. The tricycle landing gear had a wheel base of 10 feet, 1 inch (3.073 and the tread was 12 feet, 0 inches (3.658 meters). The S-51 had an empty weight of 4,050 pounds (1,837 kilograms) and maximum gross weight of 5,300 pounds (2,404 kilograms) below 1,000 feet (305 meters) MSL.³ Fuel capacity was 100 gallons (379 liters).

The H-5F was powered by an air-cooled, supercharged, 986.749-cubic-inch-displacement (16.170 liter) Pratt & Whitney R-985 AN-5 (Wasp Jr. T1B4 ) which was placed in the fuselage behind the crew compartment with the crankshaft vertical. The R-985-AN-5 was a direct-drive, nine-cylinder radial engine with a compression ratio of 6:1. It required 91-octane aviation gasoline and was rated at 450 horsepower at 2,300 r.p.m., Standard Day at Sea Level. The R-985 AN-5 was 48.00 inches (1.219 meters) long, 46.25 inches (1.175 meters) in diameter and weighed 684 pounds (310.3 kilograms) with a magnesium crankcase.

The H-5F had a maximum speed (V_NE) of 107 knots (123 miles per hour/198 kilometers per hour). Range was 275 miles (443 kilometers). The service ceiling was 14,800 feet (4,511 meters). The absolute hover ceiling was 3,000 feet (914 meters).

¹ Reorganized as the 3rd Air Rescue Squadron 10 August 1950.

² An 8 foot, 9 inch (2.667 meter) all-metal two-blade tail rotor assembly became standard with the H-5G, and was available to retrofit earlier helicopters.

³ The maximum gross weight had to be reduced 150 pounds (68 kilograms) for each additional 1,000 feet of altitude.

11 March–6 April 1949

April 6, 2024Aviation51-234, Air Station, Helicopter, Port Angeles, Pratt & Whitney R-985 AN-5, Pratt & Whitney Wasp Jr. T1B4, Robert McAuliife, Sikorsky Aircraft Corporation, Sikorsky HO3S-1G, Sikorsky S-51, Stewart R. Graham, Stewart Ross Graham, Transcontinental Flight, United States Coast Guard, USCGBryan Swopes

Lieutenant Stewart R. Graham, USCG, in cockpit of Sikorsky HNS-1 near Gander, Newfoundland, September 1946. (U.S. Coast Guard)

April 6, 1949: Lieutenant Stewart Ross Graham, United States Coast Guard, and his crewman, Aviation Metalsmith 2nd Class (AM2) Robert McAuliffe, completed the longest unescorted helicopter flight on record. They flew a Sikorsky HO3S-1G, serial number 51-234, from the Coast Guard Air Station, Elizabeth City, North Carolina, to Coast Guard Air Station Port Angeles, Washington, via San Diego, California, covering a distance of 3,750 miles (6,035 kilometers) in 57.6 flight hours over 11 days.

Lieutenant Graham was the first pilot to fly a helicopter from a ship. On 16 January 1944, he flew a Sikorsky YR-4B, serial number 46445, from the deck of a British freighter, SS Daghestan, while in convoy from New York to Liverpool. After 30 minutes, he returned to the freighter. He was a pioneer in the use of the helicopter by the Coast Guard and the Navy.

U.S. Coast Guard Sikorsky HO3S-1G 51-232. (U.S. Coast Guard) — U.S. Coast Guard Sikorsky HO3S-1G 51-232, sister ship of 51-234. (U.S. Coast Guard)

The HO3S (Sikorsky S-51) was a second-generation helicopter, capable of carrying a pilot and up to three passengers. The cabin was built of aluminum with Plexiglas windows. The fuselage was built of plastic-impregnated plywood, and the tail boom was wood monocoque construction.

The main rotor consisted of three fully-articulated blades built of metal spars and plywood ribs and covered with two layers of fabric. (All metal blades soon became available.) The three bladed semi-articulated tail rotor was built of laminated wood. The main rotor turned counter-clockwise, as seen from above. (The advancing blade is on the helicopter’s right.) 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 41 feet, 7.5 inches (12.687 meters). The main rotor had a diameter of 48 feet (14.630 meters) and tail rotor diameter was 8 feet, 5 inches (2.2.565 meters) giving the helicopter an overall length of 57 feet, 1 inch (17.399 meters). It was 13 feet, 1.5 inches (4.001 meters) high. The landing gear tread was 12 feet (3.7 meters).

The S-51 had an empty weight of 4,050 pounds (1,837.05 kilograms) and maximum takeoff weight of 5,500 pounds (2,494.76 kilograms). Fuel capacity was 100 gallons (378.5 liters).

The helicopter was powered by an air-cooled, supercharged, 986.749-cubic-inch-displacement (16.170 liter) Pratt & Whitney R-985 AN-5 (Wasp Jr. T1B4) direct-drive, nine-cylinder radial engine which was placed vertically in the fuselage behind the crew compartment. This engine had a compression ratio of 6:1 and was rated at 450 horsepower at 2,300 r.p.m., Standard Day at Sea Level. The R-985 AN-5 was 48.00 inches (1.219 meters) long, 46.25 inches (1.175 meters) in diameter and weighed 684 pounds (310.3 kilograms) with a magnesium crankcase.

Sikorsky built 220 helicopter of the S-51 series.

SIKORSKY HO3S-1G — U.S. Coast Guard HO3S-1G, serial number 51-238, sister ship of Lieutenant Graham’s record-setting helicopter. (USCG/Smithsonian Institution)

16 February 1946

February 16, 2024Aviationc/n 5101, Dimitry D. Viner, First Flight, Helicopter, Jimmy Viner, NC92813, NX92800, Pratt & Whitney R-985 AN-5, Pratt & Whitney Wasp Jr. T1B4, Prototype, Sikorsky Aircraft Corporation, Sikorsky S-51, Test PilotBryan Swopes

The prototype Sikorsky S-51 commercial helicopter, NX19800, in flight between Bridgeport and East Hartford, Connecticut, 1946. (Sikorsky Historical Archive) — The prototype Sikorsky S-51 commercial helicopter, NX92800, in flight between Bridgeport and East Hartford, Connecticut, 1946. (Sikorsky Historical Archive)

16 February 1946: The Sikorsky S-51 prototype, NX92800, made its first flight. The test pilot was Dimitry D. (“Jimmy”) Viner, who later made the first civilian rescue using a helicopter. The S-51 was the first helicopter intended for commercial use, though it was also widely used by military services worldwide. (The prototype was later delivered to Aéronavale, French Naval Aviation.)

Dimitry D. ("Jimmy") Viner with a Sikorsky S-51, the civil version of the R-5. (Sikorsky Historical Archive) — Dimitry D. (“Jimmy”) Viner with a Sikorsky S-51, the civil version of the R-5. (Sikorsky Historical Archive)

The S-51 was a commercial version of the Sikorsky R-5 series military helicopters. It was a four-place, single engine helicopter, operated by one pilot. The cabin was built of aluminum with Plexiglas windows. The fuselage was built of plastic-impregnated plywood, and the tail boom was wood monocoque construction.

Sikorsky S-51 three-view illustration with dimensions. (Sikorsky Historical Archives)

The helicopter’s fuselage was 41 feet, 1¾ inches (12.541 meters). The main rotor had a diameter of 48 feet, 0 inches (14.630 meters) and tail rotor diameter was 8 feet, 5 inches (2.568 meters) giving the helicopter an overall length of 57 feet, ½ inch (17.386 meters). It was 12 feet, 11-3/8 inches (3.947 meters) high. The landing gear tread was 12 feet, 0 inches (3.658 meters).

The S-51 had an empty weight of 4,050 pounds (1,837.05 kilograms) and maximum takeoff weight of 5,500 pounds (2,494.76 kilograms). Fuel capacity was 100 gallons (378.5 liters).

Sikorsky S-51 NC92813, Los Angeles Airways, departs on a commercial flight, Los Angeles, California, 1947. (LAT) — Sikorsky S-51 NC92813, Los Angeles Airways, departs on a commercial flight, Los Angeles, California, 1947. (Los Angeles Times)

The helicopter was powered by a 986.749-cubic-inch-displacement (16.170 liter) air-cooled, supercharged, Pratt & Whitney Wasp Jr. T1B4 (R-985 AN-5) direct-drive, nine-cylinder radial engine which was placed vertically in the fuselage behind the crew compartment. This engine had a compression ratio of 6:1 and was rated at 450 horsepower at 2,300 r.p.m., Standard Day at Sea Level. The R-985 AN-5 was 48.00 inches (1.219 meters) long, 46.25 inches (1.175 meters) in diameter and weighed 684 pounds (310.3 kilograms) with a magnesium crankcase.

The S-51 had a maximum speed (V_NE) of 107 knots (123.1 miles per hour/198.2 kilometers per hour). Range was 275 miles (442.6 kilometers). The service ceiling was 14,800 feet (4,511 meters). The absolute hover ceiling was 3,000 feet (914.4 meters).

Of 220 helicopters in the S-51 series built by Sikorsky, 55 were commercial models. Westland built another 159 helicopters under license.

One of Los Angeles Airways' Sikorsky S-51 helicopters takes off from roof of the the Terminal Annex Post Office, Los Angeles, California, 1 October 1947. (Los Angeles Times Photographic Archive/UCLA Library) — One of Los Angeles Airways’ Sikorsky S-51 helicopters takes off from roof of the the Terminal Annex Post Office, Los Angeles, California, 1 October 1947. (Los Angeles Times Photographic Archive/UCLA Library)

Дмитро Дмитрович Вінер (Dimitry Dimitrovich Viner) was born in Kiev, Ukraine, Imperial Russia, 2 October 1908. He was the son of Dimitry Nicholas Weiner and Helen Ivan Sikorsky Weiner, a teacher, and the sister of Igor Ivanovich Sikorsky.

At the age of 15 years, Viner, along with his mother and younger sister, Galina, sailed from Libau, Latvia, aboard the Baltic-American Line passenger steamer S.S. Latvia, arriving at New York City, 23 February 1923.

“Jimmy” Viner quickly went to work for the Sikorsky Aero Engineering Company, founded by his uncle, Igor Sikorsky.

Dimitry Viner became a naturalized United States citizen on 27 March 1931.

Viner married Miss Irene Regina Burnett. They had a son, Nicholas A. Viner.

On 29 November 1945, Jimmy Viner and Captain Jackson E. Beighle, U.S. Army, flew a Sikorsky YR-5A to rescue two seamen from an oil barge which was breaking up in a storm off of Fairfield, Connecticut. This was the first time that a hoist had been used in an actual rescue at sea.

A Sikorsky R-5 flown by Jimmy Viner with Captain Jack Beighle, lifts a crewman from Texaco Barge No. 397, aground on Penfield Reef, 29 November 1945. (Sikorsky Historical Archive)

In 1947, Viner became the first pilot to log more than 1,000 flight hours in helicopters.

Dimitry Dimitry Viner died at Stratford, Connecticut, 14 June 1998, at the age of 89 years.