B-17 Upper Machine Gun Turret (Type A-1A)

This turret was one of the first fully-powered machine gun turret designs used to equip American aircraft and was used initially on the B-17E Flying Fortress. It is operated by an electro-hydraulic system, which powers both elevation and traverse of the turret's two .50-cal. M2 Browning machine guns, and has a rate of fire of 1,400-1,600 rounds per minute. Turrets of this and later types gradually replaced manually-operated machine guns introduced for bomber defense during the First World War, and so made the bomber and more formidable opponent to attacking fighters. This turret was manufactured by the Emerson Manufacturing Co. to a Sperry Gyroscope Co. design and was donated to the museum by the Hobart Corp. of Troy, Ohio.

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Screening at Entrance
All visitors may be screened with a metal detector upon entry. In addition all bags are subject to search and may be placed through an X-Ray machine. Weapons are not permitted including pocket knives and firearms, to include conceal carry and other dangerous weapons.
Prohibited Items
Prohibited Items:
- Firearms*
- Knives
- Box cutters
- Food and Soda Drinks
- Alcohol
- Coolers
- Backpacks

* Firearms, to include conceal carry and other dangerous weapons, are specifically prohibited in Federal facilities in accordance with 18 USC §930 (c)

Permitted Items:
- Water bottles (clear, sealed bottle, up to 20 oz.)
- Purses
- Camera bags
- Diaper bags
- Strollers
- Service animals

Please note the National Museum of the U.S. Air Force is not responsible for items left in vehicles.
Click here for frequently asked questions regarding items permitted inside the museum.
Visitor Photography Notice
Notice: Visitors may be filmed, photographed or recorded by the U.S. Air Force for educational and promotional uses, including for posting on public websites and social media.
Individuals are permitted to take their own photographs or videos while touring the museum.