What Ng percentage is required to rise above for the condition lever to switch to ground idle?

The correct answer is 13%. In the Pilatus PC-12 NG, the condition lever must reach a Ng (gas generator speed) percentage above 13% for it to switch to the ground idle configuration. This requirement is crucial as it ensures the engine has stabilized enough to operate safely at idle power on the ground, which is necessary for various operational scenarios, including taxiing and pre-flight checks.

Understanding the proper Ng percentage for switching to ground idle is part of ensuring the engine operates within its designed parameters and helps maintain safety during ground operations. Each engine's operating characteristics dictate these values, and in the case of the Pilatus PC-12 NG, the threshold of 13% reflects the manufacturer's specifications for optimal performance and reliability when transitioning from a higher to a lower power setting.