Engine overspeed or other engine underspeed in AB212 or UH1N
Hello,
Anyone got ideas how to differentiate engine overspeed or engine underspeed in non electronic controlled engines like AB212 or UH1N?
According to manual:
ENGINE OVERSPEED/FUEL CONTROL/GOVERNOR FAILURE
INDICATIONS:
1. High ENG RPM (N2) and ROTOR RPM ( N R ), possibly with
RPM caution light.
2. Definite TORQUE split (proportional to power demand).
3. High GAS PROD RPM (N1), ITT, and TORQUE of affected
engine.
4. Return of ENG RPM (N2) and ROTOR RPM ( N R ) to governed
value (if power demand is very high).
But if it's the case of engine overspeed, wouldn't the other unaffected engine lower torque to keep output XMSN torque the same?
For example, if I'm flying at 80% XMSN torque, I would normally be using 40% from each engine.
But N.1 engine overspeed, and its torque becomes 60%, wouldn't the other unaffected engine (N.2) lower torque to 20% to keep output XMSN at 80%?
If yes, how can I tell if it is N.1 engine overspeed or N.2 engine underspeed?