The injector of Executor is of the pintle type that was first used in the Apollo Program for the lunar module landing engine.

The second variant is the Executor Plus engine that it uses a larger exhaust nozzle optimized for vacuum operation.

[3] Executor, uses an inexpensive, expendable, ablatively cooled silica-phenolic and carbon fiber composite nozzle, and produce 260 kN of thrust.

Twelve engines were scheduled to be built in the first phase, until the first flight on board of the Haas 2 rocket in 2013.

This first ground flight of the Haas 2 rocket will be for the Google Lunar X Prize Competition.