Lawrance L-4S

Lawrance L-4S 60-hp air-cooled engine of the early 1920s was flight-tested in "Pony Blimp" airships as well as the Sperry "Messenger" airplane. It is typical of early-type radial engines that were developed following the demise of the rotary engine used during World War I.

Click here to return to the Early Years Gallery.

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

* 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.