CAD Models and Animations

CAD Models Created by John Riend

Liberty 12

CAD Models Created by Stephen Stanley

Liberty 12A

Lycoming R-680-17

Pratt & Whitney R-985

Pratt & Whitney R-1340


CAD Models Created by Randy Huff

BMW 803A


Lawrance L-1

The Lawrance L-1 was developed during 1918 for a small U.S. Navy seaplane, designed by Grover Loening and called the Kitten. The L-1 had a bore of 4.25", a stroke of 5.25", displaced 223.4 in³, produced 56.5 hp at 1,600 rpm, and weighed 147 lb. Developed further, a few L-4s were sold to the U.S. Army Air Service to power Sperry Messenger liaison airplane.


Lawrance R-1

Using nine cylinders that were virtually identical to the Lawrance L-series engines, the R-1, developed during 1919, displaced 670.3 in³, produced 147 hp at 1,600 rpm and weighed 438 lb. The R-1 had three Stromberg M4 carburetors, each supplying three cylinders. Four R-1s were built, and one passed a 50-hour endurance test in 1921.



Lawrance J-1

The U.S. Navy issued Lawrance a contract on 28 Feb 1920 for five engines, which were designated J-1. This new engine was built along the same lines as the R-1, but was larger. With a bore of 4.5" and a stroke of 5.5", the J-1 displaced 787.3 in³, produced 200 hp at 1,800 rpm, and weighed 476 lb. It had a compression ratio of 5.17:1 and a specific fuel consumption of 0.556 lb/hp/hr.
Drawing from experience with the R-1, the J-1 featured several design improvements that included a strengthened crankcase, thicker cylinder base flanges, a more generous fillet between the cylinder flange and skirt, larger valve springs, rocker arms, and crankshaft counterweight. Three Stromberg NA-S4 carburetors were used, more cooling fins were added to the cylinder head tops, and taller rocker arm attachment bosses were incorporated. The J-1 was a success that eventually led to the merger of Lawrance and Wright Aeronautical.

More on the J-1


Animations Created by Sergio Pasquali

BMW 801


BMW 803A


Daimler-Benz DB 601


Daimler-Benz DB 606


Fiat AS8


Gnome 80hp Carburetor


Junkers Jumo 205


Junkers Jumo 213


Napier Sabre


Pratt & Whitney R-4360


Siemens-Halske Sh3


Valve Gear Studies


CAD Images by Ugo Vicenzi


Animations by Ugo Vicenzi


Clerget 9B Assembly Animation (from YouTube)