The Liberty engine was America's most important contribution to aeronautical technology during World War I. Jesse G. Vincent of Packard and Elbert J. Hall of Hall-Scott co-designed it between May 30 and June 4, 1917 for the U.S. government, which wanted a standard design in 4-, 6-, 8-, and 12-cylinder versions that could be quickly mass-produced to equip U.S. combat aircraft. To ensure a workable engine in the shortest possible time, they used only proven components, with features from both Hall-Scott and Packard. They succeeded, with the first 8-cylinder engine delivered in early July.

However, demand for lower-power engines was already being met, and wartime experience showed the need for high power. Liberty-12s powered many aircraft types, but most were built for the de Havilland DH-4. Automakers Ford, Lincoln, Packard, Marmon, and Buick produced 20,748 Liberty 12s, with varying quality, before the Armistice, which insured their widespread use into the 1920s and '30s.

Display Status

This object is not on display at the National Air and Space Museum. It is either on loan or in storage.

Object Details

Date

Circa 1918

Country of Origin

United States of America

Type

PROPULSION-Reciprocating & Rotary

Designer

Elbert J. Hall
Jesse G. Vincent

Model

Liberty

Physical Description

Type: Reciprocating, 12 cylinders, V-type, Liquid-cooled
Power rating: 298 kW (400 hp) at 1,800 rpm
Displacement: 27.0 L (1,648.92 cu in)
Bore and Stroke: 127 mm (5 in.) x 178 mm (7 in.)
Weight: 383 kg (844 lb)

Dimensions

Height 105.4 cm (41.5 in.), Width 68.6 cm (27 in.), Depth 171.1 cm (67.375 in.)

Materials

Steel, Aluminum, Rubber, Paint, Phonolic, Preservative coating, Brass, Copper

Inventory Number

A19731563000

Credit Line

Transferred from the U.S. Navy, Naval Supply Center, Cheatham Annex, Williamsburg, Virginia

Data Source

National Air and Space Museum

Restrictions & Rights

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