The Sharp Nemesis NXT with "NXT" standing for "Neoteric experimental Technology," is a kit-built sport-class aircraft designed specifically for air racing. It serves as a successor to the previous model, the Sharp Nemesis, and was created by Jon Sharp, the president of Nemesis Air Racing. The Nemesis NXT is a single-engine, low-wing aircraft with retractable gear and seating for two individuals. The original design of the aircraft incorporates a Lycoming TIO-540-NXT Thunderbolt six-cylinder engine for propulsion.

The Lycoming O-540 is a family of air-cooled six-cylinder, horizontally opposed fixed-wing aircraft and helicopter engines of 541.5 cubic inches (8,874 cc) displacement, manufactured by Lycoming Engines. The engine is a six-cylinder version of the four-cylinder Lycoming O-360.