Tag Archives: Pratt & Whitney Wasp Major B6

26 March 1955

Pan American World Airways' Boeing 377-10-26 Stratocruiser serial number 15932, N1032V.
Pan American World Airways’ Boeing 377 Stratocruiser Clipper United States, N1032V.

26 March 1955: At 8:15 a.m. Saturday morning, Pan American World Airways Flight 845/26, a Boeing 377 Stratocruiser, Clipper United States, N1032V, departed Seattle-Tacoma Airport (SEA, or “SeaTac”) on a flight to Sydney, Australia, with intermediate stops at Portland, Oregon, and Honolulu, Hawaii. The airliner departed Portland (PDX) at 10:21 a.m., with a crew of 8 and 15 passengers on board.

Captain Herman S. Joslyn was in command of N1032V, with First Officer Angus Gustavus Hendrick, Jr.; Second Officer Michael F. Kerwick; Flight Engineer Donald Read Fowler; and Assistant Flight Engineer Stuart Bachman. The cabin crew were Purser Natalie R. Parker, Stewardess Elizabeth M. Thompson, and Steward James D. Peppin.

Clipper United States was cruising at 10,000 feet (3,048 meters) when a severe vibration began, lasting 5–8 seconds. The Number 3 engine (inboard, right) was violently torn off of the starboard wing. The damage to the airplane resulted in severe buffeting. The nose pitched down and airspeed increased. Captain Joslyn reduced engine power to limit airspeed. The Stratocruiser quickly lost 5,000 feet (1,524 meters). Because of damage to the engines’ electrical system, the flight engineer was not able to increase power on the remaining three engines. The Boeing 377 was too heavy at this early stage in the flight to maintain its altitude.

At 11:12 a.m. (19:12 UTC) the flight crew ditched the Stratocruiser into the north Pacific Ocean, approximately 35 miles (56 kilometers) west of the Oregon coastline. [N. 43° 48′ 15″, W. 125° 12′ 40″] The conditions were ideal for ditching,¹ but the impact was hard. Seats were torn loose, and several occupants were injured. Evacuation began and all three life rafts were inflated. The water temperature was 47 °F. (8.3  °C.).

A North American Aviation F-86F Sabre flown by Captain W. L. Parks, 142nd Fighter Interceptor Group, Oregon Air National Guard, located the scene of the ditching and observed smoke flares which led to two life rafts tied together. A Lockheed Constellation was also inbound to the scene from the south. After confirming that Air Force rescue aircraft were on the way, Captain Parks returned to Portland, very low on fuel.

Miss Natalie R. Parker (Medford Tribune)

The airliner’s purser, Miss Natalie R. Parker,² had been assisting passengers with their life vests and seat belts when the airliner hit the water. Standing in the aisle, she was thrown forward, knocking down five rows of seats as she hit them. She was badly bruised and suffering from shock.

Along with other crew members, Miss Parker assisted the passengers in abandoning the sinking Stratocruiser. After entering the water, some began to drift away. Miss Parker, despite her injuries, swam after one and towed him back to an inflated raft.

Her actions were particularly mentioned in the Civil Aeronautics Board accident investigation report:

The purser, a woman, although suffering from shock swam and towed the only seriously injured passenger to the nearest raft, some 200 feet [61 meters] distant.

—Civil Aeronautics Board Accident Investigation Report SA-304 File No. 1-0039, 15 November 1955, History of the Flight

The airliner floated for about 20 minutes before sinking. Of the 23 persons on board, four, passengers John Peterson, David Darrow, First Officer Hendrick, and Flight Engineer Fowler, died of injuries and exposure.

The survivors were rescued after two hours by the crew of USS Bayfield (APA-33), a U.S. Navy attack transport.

The U.S. Navy attack transport USS Bayfield (APA-33) during the rescue of the survivors of Pan Am Flight 845/26, 26 March 1955. A Standard Oil Co. tanker, SS Idaho Falls, stands by to assist. Two of the airliner’s life rafts are visible at the right edge of this photograph. One is at the end of the smoke trail crossing the center of the image. The other is a bright object at the right lower corner. (U.S. Coast Guard)

During the Civil Aeronautics Board hearings into the accident, Vice Chairman Joseph P. Adams commended the flight’s purser, Miss Parker:

“. . . all of us feel inspired that a fellow citizen, or just a fellow human being, can rise to such an occasion in the manner in which you did. It is most commendable, Miss Parker.”

—Civil Aeronautics Board Accident Investigation Report SA-304 File No. 1-0039, 15 November 1955, Footnote 3

Because the engine and propeller were not recovered, the exact nature of the failure could not be determined, but the most likely cause was considered to be a fracture of a propeller blade resulting in a severely unbalanced condition, followed by the violent separation of the engine from the wing. This was the fifth time that a Boeing 377 Stratocruiser had lost an engine following the failure of a hollow-steel Hamilton Standard 2J17 propeller blade.

When the flight engineer attempted to increase the propeller r.p.m. on the three engines simultaneously, an electrical overload occurred which opened the master circuit breaker. This prevented any engine power increase.

Airline stewardesses examine a cutaway model of the Boeing Stratocruiser. (Museum of History & Industry, Seattle)

Clipper United States was a Boeing Model 377-10-26, serial number 15932, registered N1032V. It was one of twenty of a specific variant built for Pan American World Airways. The airliner had been delivered to Pan Am on 21 May 1949. At the time of its loss, it had flown a total of 13,655 hours.

The Model 377 was a large, four-engine civil transport which had been developed concurrently with the Boeing B-50A Superfortress. The 377 followed the military C-97 Stratofreighter (Model 367), which used the wings, engines, landing gear and tail of the B-29. The B-50 and 377 shared the improved wings, engines and tail surfaces. The two airplanes made their first flights just 14 days apart. The Stratocruiser was operated by a flight crew of four. It was a double-deck aircraft, with the flight deck, passenger cabin and galley on the upper deck and a lounge and cargo compartments on the lower. The airliner was pressurized and could maintain Sea Level atmospheric pressure while flying at 15,500 feet (4,724 meters). The Model 377 could be configured to carry up to 100 passengers, or 28 in sleeping births.

A color photograph of a Pan American World Airways Boeing 377 Stratocruiser in flight. (Pan Am)
A Pan American World Airways Boeing 377 Stratocruiser in flight. (Boeing)

The Stratocruiser was 110 feet, 4 inches (33.630 meters) long with a wingspan of 141 feet, 3 inches (43.053 meters) and overall height of 38 feet, 3 inches (11.659 meters). The airliner had an empty weight of 83,500 pounds (37,875 kilograms) and the maximum takeoff weight was 148,000 pounds (67,132 kilograms).

N1032V was powered by four air-cooled, supercharged, 4,362.49-cubic-inch-displacement (71.488 liter) Pratt & Whitney Wasp Major B6 engines. These were four-row, 28-cylinder, radial engines with a compression ratio of 6.7:1.

The B6 had a Normal Power rating of 2,650 horsepower at 2,550 r.p.m., at 5,500 feet (1,676 meters), and Maximum Continuous Power rating of 2,800 horsepower at 2,550 r.p.m. at 3,500 feet (1,067 meters). The Takeoff Power rating was 3,500 horsepower at 2,700 r.p.m. with water/alcohol injection. ³

The engines drove four-bladed Hamilton Standard Hydromatic 24260 constant-speed propellers with a diameter of 17 feet (5.182 meters) through a 0.375:1 gear reduction.

The Wasp Major B6 was 4 feet, 7.00 inches (1.397 meters) in diameter and 8 feet, 0.50 inches (2.451 meters) long. It weighed 3,584 pounds (1,626 kilograms), dry. The propeller assembly weighed 761 pounds (345 kilograms).

The 377 had a cruise speed of 301 miles per hour (484 kilometers per hour) and a maximum speed of 375 miles per hour (604 kilometers per hour). During testing by Boeing, a 377 reached 409 miles per hour (658 kilometers per hour). Its service ceiling was 32,000 feet (9,754 meters) and the range was 4,200 miles (6,759 kilometers).

Boeing built 56 Model 377 Stratocruisers, with Pan American as the primary user, and another 888 military C-97 Stratofreighter and KC-97 Stratotankers.

Clipper America, a Pan American World Airways Boeing Model 377 Stratocruiser. (Boeing)

¹ Captain G.B. Cardew, master of the Matson Lines’ S.S. Hawaiian Educator, which had arrived on scene soon after the ditching, said, “The weather was perfect. The sea was calm and the sky warm and clear.”  —Oakland Tribune, Vol. CLXII, No. 86, Sunday, 27 March 1955, Page 2-A, Column 3

Natalie Parker, 1943. (Crater)

² Miss Natalie R. Parker was born 2 June 1925, the first child of Carold J. Parker, a potato chip manufacturer, and Ruth A. Parker, of Portland, Oregon. She attended Medford High School with the Class of 1943, where she was very active in extracurricular activities. Following graduation from high school, Miss Parker attended Reed College at Portland.

In 1945, Miss Parker enlisted in the United States Cadet Nurse Corps, U.S. Public Health Service, and trained as a nurse at the Johns Hopkins Hospital School of Nursing, Baltimore, Maryland. She graduated 13 June 1948.

Miss Parker joined Pan American World Airways in 1951.

Miss Natalie R. Parker married Rodney Collins Earnest, a building contractor, in Ellsworth, Maine, 21 October 1956. The wedding was officiated by Rev. S. George Bovill of the Congregational Church. They resided in Seattle, Washington. Mrs. Earnest became a founding partner and business manager of the Acorn Academy in Seattle.

³ During a demonstration of the Pratt & Whitney Wasp Major engine (military designation, R-4360) a regular production engine was taken from the assembly line and run for 22 continuous hours at 4,400 horsepower, then checked and run for another hour at 4,850 horsepower. It was then run for 100 hours at 3,000 horsepower, and 50 hours at 3,500 horsepower. When the engine was disassembled for inspection, it remained in serviceable condition.

© 2019, Bryan R. Swopes

16 October 1956

Boeing 377 Stratocruiser N90943, Pan American World Airways' Sovereign of the Skies, seen over San Francisco, circa 1947. (University of Washington Libraries Digital Collections, TRA0138)
Boeing 377 Stratocruiser N90943, Pan American World Airways’ Sovereign of the Skies, seen over San Francisco, circa 1947. (University of Washington Libraries Digital Collections, TRA0138)

16 October 1956: Pan American World Airways’ Flight 6 was a scheduled around-the-world passenger flight. The final leg, Honolulu to San Francisco, was flown by a Boeing Model 377 Stratocruiser with civil registration N90943, and named Sovereign of the Skies.

The airplane had a flight crew of 7 and carried 24 passengers. The aircraft commander was Captain Richard N. Ogg, a veteran pilot with more than 13,000 flight hours accumulated over twenty years. First Officer George L. Haaker, Flight Engineer Frank Garcia, Jr., and Navigator Richard L. Brown completed the flight crew. The cabin crew were Purser Patricia Reynolds, who had been with Pan Am for over ten years, and Stewardesses Katherine S. Araki and Mary Ellen Daniel.

The flight from Honolulu to San Francisco was estimated to take 8 hours, 54 minutes. Captain Ogg had the airplane fueled for a total flight time of 12 hours, 18 minutes.

Pan American World Airlines’ Boeing 377 Stratocruiser, Clipper America. This airplane is similar to Sovereign of the Skies. (Boeing)

Flight 6 departed Honolulu at 8:24 p.m., Hawaii Standard Time, 15 October (06:24, 16 October, GMT), and climbed to 13,000 feet (3,962 meters) on course.

4 hours, 38 minutes after takeoff, Flight 6 requested a pre-planned climb to 21,000 feet (6,400 meters), at a point about half-way—in terms of flight time—between the departure point and destination, what is dramatically called “The Point of No Return” in suspense movies. (Actually, this is called the Equal Time Point: Taking into consideration forecast winds, the time to fly back to the departing point is the same as the time to continue toward the destination.)

On leveling at the new cruise altitude at 1:19 a.m. (HST), First Officer Haaker reduced engine power. The propeller for the Number 1 engine, the outside engine on the left wing, suffered a prop governor failure and began to overspeed, with engine r.p.m. actually exceeding the limits of its tachometer. This created a very dangerous condition: If the propeller turned fast enough, it could be torn apart by centrifugal force. (See This Day In Aviation, 22 March 1956, for an example.)

The crew was unable to feather the propeller, which would cause its four blades to turn parallel to the slip stream, and increasing the load on the engine while reducing aerodynamic drag. The engine and propeller continued to turn at dangerously high speed so Captain Ogg decided to force the engine to stop by cutting off its lubricating oil supply. This caused the engine to seize but the propeller continued to “windmill.”

The drag caused by the propeller slowed the airplane considerably and the three remaining engines had to run at high power for the Boeing 377 to maintain its altitude. The Number 4 engine (the outer engine on the right wing) was developing only partial power at full throttle. At 2:45 a.m., it began to backfire and had to be shut down.

The airplane began to descend toward the ocean’s surface.

With the drag of the windmilling Number 1 propeller and only two engines running, Sovereign of the Skies could fly at just 140 knots (161 miles per hour/259 kilometers per hour), not fast enough to reach San Francisco or to return to Honolulu before running out of fuel. The navigator estimated that they would run out of fuel 250 miles (402 kilometers) from land.

The United States Coast Guard kept a high endurance cutter on station between Hawaii and California, at a point known as Ocean Station November. This ship provided assistance with weather information, radio communications and was available to assist should an emergency arise aboard trans-Pacific airplanes.

USCGC Pontchartrain (WHEC 70) circa 1958. (U.S. Coast Guard)
USCGC Pontchartrain (WHEC 70) circa 1958. (U.S. Coast Guard)

On 16 October 1956, this cutter was USCGC Pontchartrain (WHEC 70), under the command of Commander William K. Earle, USCG. Pontchartrain was a 255-foot (77.7 meter) Lake-class patrol gunboat built by the U.S. Coast Guard ship yard at Curtiss Bay, Maryland, and commissioned 28 July 1945. The ship was redesignated as a high endurance cutter in 1948. Pontchartrain had a complement of 143 men.

The ship was 254 feet (77.42 meters) long, overall, with a beam of 43 feet, 1 inch (13.13 meters) and draft of 17 feet, 3 inches (5.25 meters). Its full load displacement was 1,978 tons (1,794 Metric tons). It was powered by a Westinghouse turbo-electric drive of 4,000 shaft horsepower and was capable on making 17.5 knots (20.41 miles per hour, or 32.41 kilometers per hour). Its maximum range was 10,376 miles (19,216 kilometers).

Pontchartrain was armed with a single 5-inch/38-caliber naval gun forward. It carried Hedgehog anti-submarine mortars and Mk 23 acoustic-homing antisubmarine torpedoes.

Captain Ogg notified Ponchartrain that he intended to ditch the airliner near the ship. The Coast Guard provided Captain Ogg with wind and wave information—five-foot (1.5 meter) swells, wind at eight knots (4 meters per second) from the northwest—and advised the best heading for ditching. The ship laid a trail of foam to mark this course.

Pan American World Airways Flight 6, a Boeing 377 Stratocruiser, ditches in the North Pacific Ocean near USCGC Pontchartrain (WHEC 70), 6:15 am., 16 October 1956. (U.S. Coast Guard)
Pan American World Airways Flight 6, a Boeing 377 Stratocruiser, ditches in the North Pacific Ocean near USCGC Pontchartrain (WHEC 70), 6:15 am., 16 October 1956. (U.S. Coast Guard)

At 6:15 a.m., at approximately 90 knots airspeed (104 miles per hour/167 kilometers per hour), the Boeing 377 landed on the water. A wing hit a swell, spinning the airplane to the left. The tail broke off and the airplane began to settle.

Pan American World Airways’ Boeing 377 Stratocruiser, Sovereign of the Skies, with its fuselage broken after ditching in the North Pacific Ocean, 16 October 1956. (Pan Am Historical Foundation/The New York Times)

Injuries were minor and all passengers and crew evacuated the airliner. They were immediately picked up by Pontchartrain.

Captain Ogg and Purser Reynolds were the last to leave the airplane.

Twenty minutes after touching down, at 6:35 a.m., Sovereign of the Skies sank beneath the ocean’s surface.

Sovereign of the Seas sinks into the Pacific Ocean, 16 October 1956. (U.S. Coast Guard)
Sovereign of the Skies sinks into the Pacific Ocean, 16 October 1956. (U.S. Coast Guard)

Pan American’s Sovereign of the Skies was a Boeing Model 377-10-29, construction number 15959, originally operated by American Overseas Airlines as Flagship Holland, and later, Flagship Europe. Pan Am acquired the airliner during a merger. On 16 October 1956, the airplane had accumulated 19,820:51 total time on the airframe (TTAF) since it was built.

The Boeing 377 was a large, four-engine civil transport which had been developed, along with the military C-97 Stratofreighter, from the World War II B-29 Superfortress long-range heavy bomber. It utilized the wings and engines of the improved B-50 Superfortress. The airplane was operated by a flight crew of four. It was a double-deck aircraft, with the flight deck, passenger cabin and galley on the upper deck and a lounge and cargo compartments on the lower. The airliner was pressurized, and could maintain Sea Level atmospheric pressure while flying at 15,500 feet (4,724 meters). The Model 377 could be configured to carry up to 100 passengers, or 28 in sleeping births.

The Stratocruiser was 110 feet, 4 inches (33.630 meters) long with a wingspan of 141 feet, 3 inches (43.053 meters) and overall height of 38 feet, 3 inches (11.659 meters). Empty weight was 83,500 pounds (37,875 kilograms) and the maximum takeoff weight was 148,000 pounds (67,132 kilograms). Sovereign of the Skies had a gross weight of 138,903 pounds (63,005 kilograms) when it took off from Honolulu.

Crew members of Pan American World Airways Flight 6 receive commendations for their service during the emergency of 16 October 1956. Left to right, Captain Richard N. Ogg; Navigator Richard L. Brown; Purser Patricia Reynolds; (unidentified); First Officer George L. Haaker; Flight Engineer Frank Garcia, Jr.. (Pan Am Historical Foundation/The New York Times)

The airliner was powered by four air-cooled, supercharged 4,362.49-cubic-inch-displacement (71.489 liter) Pratt & Whitney Wasp Major B6 four-row, 28-cylinder radial engines which had a Normal Power rating of 2,650 horsepower at 2,550 r.p.m., and 2,800 horsepower at 2,550 r.p.m. Maximum Continuous. It produced 3,250 horsepower at 2,700 r.p.m. for takeoff (3,500 horsepower with water injection). The engines drove four-bladed Hamilton-Standard Hydromatic, 24260 constant-speed propellers with a diameter of 17 feet, 0 inches (5.182 meters) through a 0.375:1 gear reduction. The Wasp Major B6 was 8 feet, 0.50 inches (2.451 meters) long, 4 feet, 7.00 inches (1.397 meters) in diameter, and weighed 3,584 pounds (1,626 kilograms).

The 377 had a cruise speed of 301 miles per hour (484 kilometers per hour) and a maximum speed of 375 miles per hour (604 kilometers per hour). During testing by Boeing, a 377 reached 409 miles per hour (658 kilometers per hour). Its service ceiling was 32,000 feet (9,754 meters) and the range was 4,200 miles (6,759 kilometers).

Boeing built 56 Model 377 Stratocruisers, with Pan American as the primary user, and another 888 military C-97 Stratofreighter and KC-97 Stratotankers.

A U.S. Coast Guard film of the incident can be seen at:

© 2018, Bryan R. Swopes

8 July 1947

First flight, Boeing Model 377 Stratocruiser
First flight, Boeing Model 377 Stratocruiser NX90700, c/n 15922. After the flight test program was completed, this airplane was upgraded to the 377-10-26 standard and placed in service with Pan American World Airways as Clipper Nightingale, N1022V

8 July 1947: First flight, Boeing Model 377-10-19 Stratocruiser, Project Test Pilot John Bernard Fornasero. (Fornasero had been the co-pilot on the first flight of the XC-97 Stratofreighter, nearly three years earlier.)

Flight deck of the Boeing Model 377 Stratocruiser. (Boeing)
Flight deck of the Boeing Model 377 Stratocruiser. (Boeing)

The Model 377 was a large, four-engine civil transport which had been developed, along with the military C-97 Stratofreighter, from the World War II B-29 Superfortress long-range heavy bomber. It utilized the wings and engines of the improved B-50 Superfortress. The airplane was operated by a flight crew of four. It was a double-deck aircraft, with the flight deck, passenger cabin and galley on the upper deck and a lounge and cargo compartments on the lower. The airliner was pressurized, and could maintain Sea Level atmospheric pressure while flying at 15,500 feet (4,724 meters). The Model 377 could be configured to carry up to 100 passengers, or 28 in sleeping births.

Airline stewardesses examine a cutaway model of the Boeing 377 Stratocruiser. (Museum of History & Industry, Seattle)

The Stratocruiser was 110 feet, 4 inches (33.630 meters) long with a wingspan of 141 feet, 3 inches (43.053 meters) and overall height of 38 feet, 3 inches (11.659 meters). The airliner had an empty weight of 83,500 pounds (37,875 kilograms) and its maximum takeoff weight was 148,000 pounds (67,132 kilograms).

Boeing Model 377-10-19 Stratocruiser NX90700. (Boeing)
Boeing Model 377-10-19 Stratocruiser NX90700. (Boeing)

The 377-10-19 prototype was powered by four 4,362.49-cubic-inch-displacement (71.49 liter) air-cooled, supercharged Pratt & Whitney Wasp Major B5 four-row, 28-cylinder radial engines. This engine had a compression ratio of 6.375:1 and required 100/130 aviation gasoline. It had a Normal and Maximum Continuous Power rating of 2,650 horsepower at 2,550 r.p.m., and Take Off Power rating of 3,250 horsepower at 2,700 r.p.m. with water/alcohol injection. The Wasp Major B5 was 4 feet, 6.00 inches in diameter and 8 feet, 0.75 inches long. The engine weighed 3,490 pounds (1,583 kilograms).

The following production Stratocruisers were equipped with Pratt & Whitney Wasp Major B6 engines rated at 3,500 horsepower at 2,700 r.p.m. (with water/alcohol injection) for takeoff, and a Normal Power of 2,650 horsepower at 2,550 r.p.m., at 5,500 feet (1,676 meters). The Maximum Continuous Power rating for the B6 was 2,800 horsepower at 2,550 r.p.m. at 3,500 feet (1,067 meters). The Wasp Major B6 was 4 feet, 7.00 inches (1.397 meters) in diameter and 8 feet, 0.50 inches (2.451 meters) long. It weighed 3,584 pounds (1,626 kilograms), dry.

Pan American World Airways Boeing Model 377 Stratocruiser. (Boeing)
Pan American World Airways’ Boeing Model 377-10-26 Stratocruiser, Clipper Nightingale, N1022V, c/n 15922. (Boeing)

The engines drove four-bladed Hamilton Standard Hydromatic constant-speed propellers with a diameter of 17 feet (5.182 meters) through a 0.375:1 gear reduction. The propeller assembly weighed 761 pounds (345 kilograms).

The 377 had a cruise speed of 301 miles per hour (484 kilometers per hour) and a maximum speed of 375 miles per hour (604 kilometers per hour). During testing by Boeing, a 377 reached 409 miles per hour (658 kilometers per hour). Its service ceiling was 32,000 feet (9,754 meters) and the range was 4,200 miles (6,759 kilometers).

Lower deck passenger lounge of a Boeing 377 Stratoliner. (Boeing)
Lower deck passenger lounge of a Boeing 377 Stratoliner. (Boeing)

Boeing built 56 Model 377 Stratocruisers, with Pan American as the primary user, and another 888 military C-97 Stratofreighter and KC-97 Stratotankers.

Following the flight testing program, NX90700 was brought up to the 377-10-26 standard and placed in service with Pan American World Airways, 24 October 1950. It was named Clipper Nightingale and registered N1022V. The airliner remained in Pan Am service until 1960, when it was sold back to Boeing.

N1022V was next sold to Rutas Aéreas Nacionales, S.A. (RANSA) and converted to a freighter. The new owners named it Carlos. It was re-registered YV-C-ERI. The Stratocruiser was finally retired in 1969 and scrapped.

The prototype Boeing 377 Stratocruiser was sold to RANSA and converted to a freighter. It was named "Carlos" and registered YV-C-ERI.
The prototype Boeing 377 Stratocruiser was sold to RANSA and converted to a freighter. It was named “Carlos” and registered YV-C-ERI.

© 2019, Bryan R. Swopes