| Liberty L-6 | |
|---|---|
 | |
| Liberty L-6 aircraft engine on display at theNational Museum of the United States Air Force | |
| Type | Pistonaero engine |
| National origin | United States |
| Manufacturer | Wright Aeronautical,Thomas-Morse Aircraft |
| Designer | Jesse G. Vincent andElbert J. Hall |
| First run | about 1917 |
| Major applications | Engineering Division TW-1 |
| Number built | 52 |
| Variants | Liberty L-4,Liberty L-8,Liberty L-12 |
TheLiberty L-6 was a six-cylinderwater-cooledinlineaircraft engine developed in the United States duringWorld War I.
The Liberty L-6, which developed 200–215 hp, was built by theThomas-Morse Aircraft Corp. andWright Aeronautical Corp. Since it was based on the same engine design as the more successfulLiberty L-12V-12 liquid-cooled aviation engine, the L-6's resemblance to theMercedes D.III German aviation engine, the source for the Liberty V-12's own cylinder and valvetrain design, resulted in the American L-6 engine design bearing a close visual resemblance to the German straight-six aviation powerplant in a number of respects, with at least one L-6 even being mounted postwar into a capturedFokker D.VII fighter for testing in the US. The Liberty L-6's smaller displacement of some 825 cu. in. (13.5 liters) versus the late-war German Mercedes D.IIIaü's 903 cubic inches (14.8 liters) do not seem to have handicapped the American straight-six design, however, as the "Liberty Six" possessed a 5.42:1CR, while the D.IIIaü had only a 4.64:1 CR, explaining a good bit of the American powerplant's output level—in addition to the 735.5 watt level for GermanPferdestärke metric horsepower, versus the then solely-American-basedSAE organization's standard of almost 746 watts per one horsepower.
Since the L-6 was too large for mail airplanes and other engines were available, the L-6 was canceled after only 52 had been built. In 1920 10 more L-6 engines were ordered, designated L-825, several of which were installed in theCurtiss PN-1, (only two built), and theEngineering Division TW-1, (only six built).
Hall-Scott also produced a six-cylinder engine using Liberty L-12 components, as theHall-Scott L-6.
Comparable engines
Related lists
This article incorporates text fromLiberty L-6, a public domain work of the United States Government.