DARPA awarded Pratt & Whitney a $33.8 million contract to develop Constant Volume Combustion (CVC) engine technology under Phase II of the Vulcan advanced propulsion program. While conventional engines burn fuel at a constant pressure, CVC engines combust fuel at a constant volume and are significantly more efficient than conventional engines. The goal of the Vulcan demonstration program is to design, build, and ground test a CVC technology system that demonstrates a 20% fuel-burn reduction for a ship-based power generation turbine. CVC, when combined with jet turbine engines, offers the ability to design a new class of hybrid turbine power generation engines for naval ships and air-breathing aircraft engines. During Phase II, the CVC module will be developed, fabricated, tested, and fully characterized through analytical models as well as component and subsystem testing prior to the final integration into the turbine engine for U.S. naval surface vessels.