V1650

V1650 is the Packard designation for the license-built Rolls-Royce Merlin 60-series V-12 aircraft engine. It has a displacement of 27.0 liters (1,650 cubic inches) and is a liquid-cooled, 12-cylinder V engine with overhead camshafts and four valves per cylinder. In its later variants, it employed a two-stage, two-speed supercharger to maintain high-altitude performance.

The V1650 was produced in the United States by Packard under license from Rolls-Royce during World War II and was used in several Allied aircraft. The most famous application is the North American P-51 Mustang, where the V1650 significantly improved range and high-altitude capability, contributing to the Mustang’s success as a long-range escort fighter. The engine family included multiple Packard variants designed for different power ratings and altitude requirements, reflecting the needs of various airframes and mission profiles.

Technical characteristics of the V1650 connect it to the Merlin lineage, sharing many design features such as the four-valve-per-cylinder configuration and depth of cooling and fuel control adjustments that allowed it to operate effectively across a wide altitude band. The engine’s combination of reliability, power density, and the high-altitude performance provided by the supercharged Merlin design was a key factor in Allied air operations from the mid-war period onward.

In historical context, the V1650’s development and deployment exemplify wartime licensing arrangements that facilitated rapid scale-up of advanced aero-engine technology and helped shape the outcome of air campaigns in Europe.