Boeing Monomail facts for kids

Kids Encyclopedia Facts
Model 200 and 221 Monomail
A United Airlines Model 221
Role Airliner
Manufacturer Boeing
First flight 6 May 1930
Retired 1933
Status Retired
Primary user United Airlines
Number built 2
Developed into Boeing YB-9

The Boeing Model 200 Monomail was an American mail plane. It was built in the 1930s by Boeing. It flew for the first time on 6 May 1930.

Design and development

The Boeing Monomail was a monoplane instead of a biplane. Its wheels could be retracted. Only one plane was made for the US Army to look at. The plane eventually began to fly main from San Francisco to Chicago.

Another version was made, the Model 221. It was made longer by 8 inches. This meant it could carry passengers, but less cargo. This version first flew on 18 August 1930.

There were no good engines for the Boeing Monomail to use. By the time good engines could be used, new planes had been made which were better than the Monomail. One of these was the Boeing 247.

Types of Boeing Monomail

Model 200
mailplane (one was built)
Model 221
mailplane which could carry six passengers (one was built)
Model 221A
Model 200 and 221 changed into airliners


 United States
  • Boeing Air Transport
  • United Air Lines

Details (Model 221)

General characteristics

  • Crew: 1
  • Capacity: 6
  • Length: 41 ft 10 in (12.75 m)
  • Wingspan: 59 ft 1 in (18 m)
  • Height: ()
  • Max. takeoff weight: 8,000 lb (3,628.7 kg)
  • Powerplant: 1 × Pratt & Whitney Hornet B, 575 hp (428.8 kW)


  • Maximum speed: 158 mph (254 km/h)
  • Cruise speed: 135 mph (217 km/h)
  • Range: 575 mi (925 km)
  • Service ceiling: 14,700 ft (4,480.5 m)

Boeing Monomail Facts for Kids. Kiddle Encyclopedia.