Donald Roebling and the Origins of the Amphibious Tractor


Donald Roebling was the great grandson of fabled bridge engineer John Augustus Roebling, who designed the Brooklyn Bridge. He grew up in Bernardsville, New Jersey and moved to Clearwater, Florida in 1929. His arrived about six months after the Great Lake Okeechobee Hurricane of September 16, l928, which swept across Lake Okeechobee, inundating newly developed tracts, killing 1,836 a residents and causing $25 million in damages. Many of the storm's victims expired after the hurricane because rescuers were unable to reach them across so many miles of flooded, muddy backswamps created by the storm. Roebling realized that an amphibious vehicle that could travel on land, swamps, and across deep water might have saved hundreds of lives. Between 1933-37 Roebling supervised the construction of four increasingly sophisticated amphibious tractors, culminating in the Alligator, which weighed 8,700 pounds. It employed curved cleats, which allowed it to achieve a water speed of 8.6 mph and a land speed of 18 mph. It was this critical part of the propulsion systems that Roebling took the effort to patent. The tractor was featured in LIFE magazine and caught the attention of the U.S. Marine Corps, which eventually led to the Alligator being produced in substantial quantities for American amphibious operations in World War II, where they came to be known as "Amtracs.".

Meeting Name

16th World Environmental and Water Resources Congress: Professional Development, Innovative Technology, International Perspectives, and History and Heritage (2016: May 22-26, West Palm Beach, FL)


Geosciences and Geological and Petroleum Engineering

Keywords and Phrases

Amphibious Vehicles; Bridges; Environmental Technology; Hurricanes; Innovation; Lakes; Military Operations; Patents And Inventions; Storms; Tractors (Agricultural); Tractors (Truck); Amphibious Operations; Bridge Engineer; Brooklyn Bridge; Great Lakes; Lake Okeechobee; Propulsion System; U.S. Marine Corps; World War II; Water Resources

International Standard Book Number (ISBN)


Document Type

Article - Conference proceedings

Document Version


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© 2016 American Society of Civil Engineers (ASCE), All rights reserved.

Publication Date

01 May 2016