rotor inertia. If the rotor has high rotational 
energy the rotor will lose RPM less rapidly, 
giving the pilot more time to reduce collective 
pitch and enter autorotation. If the rotor has 
low rotational energy, the rotor will lose RPM 
rapidly and the pilot may not be able to react 
quickly enough to prevent a serious loss of 
rotor RPM. Once the collective pitch is at