The secondary passages on the gas turbine engine fuel nozzles shown in the illustration are designed to open at approximately what pressure? Illustration GT-0005

Correct Answer: Option D — 330 PSIG

Dual-orifice fuel nozzles utilize a primary and secondary flow path to optimize atomization across the engine's operating range. The secondary passage is spring-loaded and calibrated to open at approximately 330 PSIG, allowing increased fuel flow as the Gas Generator speed and power demand rise during acceleration.