Tag Archives: Pratt & Whitney Wasp S1H1-G

8 February 1933

Boeing 247 NC13300 (Boeing)
Boeing 247 NC13300 (Boeing)

8 February 1933: Boeing test pilot Leslie R. (“Les”) Tower and United Air Lines Captain Louis C. Goldsmith made the first flight of the Boeing Model 247, NX13300, a twin-engine airline transport, at Boeing Field, Seattle, Washington. The first flight lasted 40 minutes and Tower was quite pleased with the airplane. He took it up a second time later in the day.

The Boeing Model 247 instrument panel used gyroscopic-stabilized instruments for instrument flight. (Unattributed)
The Boeing Model 247 instrument panel used gyroscopic-stabilized instruments for instrument flight. (Boeing)

The 247 is considered to be the first modern airliner because of its all-metal semi-monocoque construction, cantilevered wing and retractable landing gear. It was 50 miles per hour (80.5 kilometers per hour) faster than its contemporaries, and could climb on one engine with a full load.

The airplane was built at Boeing’s Oxbow factory on the Duwamish River, then barged to Boeing Field where it was assembled and tested. The 247 was originally named “Skymaster,” but this was soon dropped.

Two months after the first flight, the first production 247, NC13301, was placed in service with United Air Lines. It was the first of ten 247s bought by United.

This postcard illustration shows the interior arrangement of a Boeing 247 airliner. (United Air Lines)
This postcard illustration shows the interior arrangement of a Boeing 247 airliner. (United Air Lines)

The Model 247 was operated by a pilot, co-pilot and a flight attendant and carried up to ten passengers. The airplane was 51 feet, 5 inches (15.672 meters) long, with a wingspan of 74 feet, 1 inch (22.581 meters) and overall height of 12 feet, 5 inches (3.785 meters). The empty weight was 8,921 pounds (4,046.5 kilograms) with a maximum takeoff weight of 16,805 pounds (7,622.6 kilograms).

The Duralamin skin panels were anodized, rather than painted, for corrosion protection. This saved weight, and resulted in the 247’s characteristic gray-green color.

Boeing 247 NC13301. (Boeing)

The airliner was powered by two air-cooled, supercharged, 1,343.804-cubic-inch-displacement (22.021 liters) Pratt & Whitney Wasp S1H1-G nine-cylinder radial engines with a compression ratio of 6.03:1. The S1H1-G 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 Takeoff. They drove three-bladed Hamilton Standard constant-speed propellers through a 3:2 gear reduction. The Wasp S1H1-G was 3 feet, 11.80 inches (1.214 meters) long, 4 feet, 3.61 inches (1.311 meters) in diameter, and weighed 930 pounds (422 kilograms).

The Boeing 247 had a maximum speed of 200 miles per hour (321.9 kilometers per hour) with a cruising speed of 188 miles per hour (302.6 kilometers per hour. It had a range of 745 miles (1,199 kilometers) and a service ceiling of 25,400 feet (7,742 meters).

A contemporary photo post card depicts United Air Lines stewardesses with a Boeing Model 247 airliner. The post mark on the reverse side is faintly visible.
A contemporary photo post card depicts ten United Air Lines stewardesses with a Boeing Model 247 airliner. The post mark on the reverse side is faintly visible. (United Air Lines)

75 Model 247s were built. 60 were bought by Boeing Air Transport.

NC13301, the first production Boeing Model 247 airliner. (NASM)

[Note: the windshield was canted forward to prevent instrument panel lighting from reflecting into the cockpit at night. Unfortunately, ground lighting was reflected instead. This was soon changed to a rearward slant and resulted in a slight increase in speed.]

Boeing 247 NC13300 (aviadejavu.ru)

© 2019, Bryan R. Swopes

12 January 1937

Wreck of Western Air Express Boeing 247D NC13315, Los Pinetos Peak, near newhal, California, 12 January 1937. (Santa Clarita Valley History in Pictures)
Wreck of Western Air Express Flight 7, a Boeing Model 247D, NC13315, at Los Pinetos Peak near Newhall, California, 12 January 1937. (Santa Clarita Valley History in Pictures)

12 January 1937: Western Air Express Flight 7, a Boeing 247D airliner, NC13315, had originated at Salt Lake City, Utah, and after a stop at Las Vegas, Nevada, continued on toward Union Air Terminal, Burbank, California. Aboard were a crew of three and ten passengers.

In fog and falling snow, Captain William Walker Lewis and co-pilot Clifford P. Owens crossed over Saugus, California,

“. . . at 5,200 feet [1,585 meters], aircraft was already 300 feet [91 meters] too low. . . Pilot tried to contact Burbank without any success. Due to low visibility caused by fog, pilot did not realize he was flying at an insufficient altitude. In a descent rate of 525 feet per minute [2.667 meters per second], aircraft hit Pinetos Peak.”

— Bureau of Air Commerce report.

According to statements after the accident, Captain Lewis suddenly saw a ridge immediately ahead, and unable to avoid it, cut his engines and raised the nose in an attempt to reduce the impact. The accident occurred at 11:07 a.m., Pacific Time.

Illustration from the Los Angeles Times, Vol. LVI, Wednesday, 13 January 1937, Page 6, Columns 3–6.

The crash was heard by patients at the Olive View Sanitorium and ranchers on the north side of the mountains. Two hours later, passenger Arthur S. Robinson arrived at the hospital and said, “Get help up there for the twelve others. It was a forced landing—they’re all injured but I believe they’re all alive.”

Boeing 247D NC13315, 12 January 1937. (Santa Clarita Valley History in Pictures)
Boeing 247D NC13315, 12 January 1937. (Santa Clarita Valley History in Pictures)

One passenger, James A. Braden, president of the Braden-Sutphin Ink Co., of Cleveland, Ohio, was killed immediately. The co-pilot, Owens, and three more of the passengers died of injuries within the next several days.

One of those who died was famed adventurer and film maker Martin Johnson. His wife, Osa Johnson, was also aboard Flight 7 and was seriously injured. Another survivor, Robert T. Anderson, would later own Pea Soup Anderson, a famous restaurant in Buellton, California.

Osa and Martin Johnson. (Osa and Martin Johnson Safari Museum)
Osa and Martin Johnson. (Osa and Martin Johnson Safari Museum)

The Boeing Model 247 is considered to be the first modern airliner because of its all-metal, semi-monocoque construction, cantilevered wing and retractable landing gear. It was 50 miles per hour (80 kilometers per hour) faster than its contemporaries, and could climb on one engine with a full load.

The Model 247 was operated by a pilot, co-pilot and a flight attendant and carried up to ten passengers. The airplane was 51 feet, 5 inches (15.672 meters) long, with a wingspan of 74 feet, 1 inch (22.581 meters) and overall height of 12 feet, 5 inches (3.785 meters). The empty weight was 8,921 pounds (4,046.5 kilograms) with a maximum takeoff weight of 16,805 pounds (7,622.6 kilograms).

The Duralamin skin panels were anodized, rather than painted, for corrosion protection. This saved weight, and resulted in the 247’s characteristic gray-green color.

Western Air Express Boeing 247D NC13315. The nose baggage compartment door is open. (Ed Coates Collection)
Western Air Express Boeing 247D NC13315. The nose baggage compartment door is open. (Ed Coates Collection)

The airliner was powered by two air-cooled, supercharged, 1,343.804-cubic-inch-displacement (22.021 liters) Pratt & Whitney Wasp S1H1-G nine-cylinder radial engines with a compression ratio of 6.03:1. The S1H1-G 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 Takeoff. They drove three-bladed Hamilton Standard constant-speed propellers through a 3:2 gear reduction, when installed on the 247D. The Wasp S1H1-G was 3 feet, 11.80 inches (1.214 meters) long, 4 feet, 3.61 inches (1.311 meters) in diameter, and weighed 930 pounds (422 kilograms).

The Boeing 247 had a maximum speed of 200 miles per hour (322 kilometers per hour) with a cruising speed of 188 miles per hour (303 kilometers per hour. It had a range of 745 miles (1,199 kilometers) and a service ceiling of 25,400 feet (7,742 meters).

75 Model 247s were built. 60 were operated by Boeing Air Transport.

[Note: the windshield was canted forward to prevent instrument panel lighting from reflecting into the cockpit at night. Unfortunately, ground lighting was reflected instead. This was soon changed to a rearward slant and resulted in a slight increase in speed.]

Western Air Express Boeing 247D NC13315, 1933. (SCVhistory.com)
Western Air Express Boeing 247D NC13315, 1933. (Santa Clarita Valley History in Pictures)

© 2019, Bryan R. Swopes