In 1925, Boeing built its first Model 40 in response to a U.S. Post Office competition for a design to replace war surplus de Havilland DH-4s. The specification required using the World War I-era Liberty engine. The Model 40 first flew in July 1925, and the Post Office purchased the single airframe, but no more. However, the Kelly Act of 1925 opened up air mail to private ventures, stimulating a new industry.

In late 1926, when the Chicago-San Francisco airmail contract went for bid, former Boeing pilot and experienced mailplane operator Eddie Hubbard approached the company's chief engineer, Claire Egtvedt, with a business proposal. Together, they revisited the Model 40 design. A two-seat passenger compartment was added, the fuselage structure was redesigned with welded steel tubing, and -- most importantly -- the water-cooled Liberty engine was replaced with the new and efficient Pratt & Whitney air-cooled Wasp. Hubbard and Egtvedt convinced William Boeing that the improved Model 40 would enable the firm to win the transcontinental contract.

Boeing indeed won the business with the new airplane, dubbed Model 40A. The newly formed Boeing Air Transport would conduct the operation, beginning in July 1927. It was immediately profitable; asked how he could operate so efficiently, Boeing said, "I would rather fly 200 more pounds of mail than water." In addition to mail, the two-passenger compartment created a market of its own. Later versions of the 40 flew with a more powerful Pratt & Whitney Hornet and room for four passengers. Over time, 40As were upgraded to the Hornet and called 40B, later 40B-2 after introduction of the four-passenger 40B-4.

The Boeing Model 40 was the company's first major commercial success, ensuring Boeing a place in the rapidly growing civil market of the late 1920s. It also cemented a long-lasting relationship with engine-maker Pratt & Whitney. A total of 77 Model 40s were built between 1925 and 1932.

Thanks to the generosity of William E. Boeing Jr., the Museum's Model 40B reproduction was constructed by Century Aviation of Wenatchee, Washington, and was installed in our Great Gallery in October of 2007.

Wingspan:
44.17ft
Length:
33ft
Height:
12ft
Wing Area:
547.00ft²
Empty Weight:
3,722lbs
Gross Weight:
6,075lbs
Maximum Speed:
137mph
Cruise Speed:
125mph
Power Plant:
One Pratt & Whitney R-1690 "Hornet" engine
Range:
535miles

In 1925, Boeing built its first Model 40 in response to a U.S. Post Office competition for a design to replace war surplus de Havilland DH-4s. The specification required using the World War I-era Liberty engine. The Model 40 first flew in July 1925, and the Post Office purchased the single airframe, but no more. However, the Kelly Act of 1925 opened up air mail to private ventures, stimulating a new industry.

In late 1926, when the Chicago-San Francisco airmail contract went for bid, former Boeing pilot and experienced mailplane operator Eddie Hubbard approached the company's chief engineer, Claire Egtvedt, with a business proposal. Together, they revisited the Model 40 design. A two-seat passenger compartment was added, the fuselage structure was redesigned with welded steel tubing, and -- most importantly -- the water-cooled Liberty engine was replaced with the new and efficient Pratt & Whitney air-cooled Wasp. Hubbard and Egtvedt convinced William Boeing that the improved Model 40 would enable the firm to win the transcontinental contract.

Boeing indeed won the business with the new airplane, dubbed Model 40A. The newly formed Boeing Air Transport would conduct the operation, beginning in July 1927. It was immediately profitable; asked how he could operate so efficiently, Boeing said, "I would rather fly 200 more pounds of mail than water." In addition to mail, the two-passenger compartment created a market of its own. Later versions of the 40 flew with a more powerful Pratt & Whitney Hornet and room for four passengers. Over time, 40As were upgraded to the Hornet and called 40B, later 40B-2 after introduction of the four-passenger 40B-4.

The Boeing Model 40 was the company's first major commercial success, ensuring Boeing a place in the rapidly growing civil market of the late 1920s. It also cemented a long-lasting relationship with engine-maker Pratt & Whitney. A total of 77 Model 40s were built between 1925 and 1932.

Thanks to the generosity of William E. Boeing Jr., the Museum's Model 40B reproduction was constructed by Century Aviation of Wenatchee, Washington, and was installed in our Great Gallery in October of 2007.

Wingspan:
44.17ft
Length:
33ft
Height:
12ft
Wing Area:
547.00ft²
Empty Weight:
3,722lbs
Gross Weight:
6,075lbs
Maximum Speed:
137mph
Cruise Speed:
125mph
Power Plant:
One Pratt & Whitney R-1690 "Hornet" engine
Range:
535miles