WE CLAIM
1. A method for determining an engine heath factor of an aircraft engine
comprising:
determining, by one or more control devices, an engine condition indicative of an engine health during operation of the aircraft engine;
accessing, by the one or more control devices, a baseline engine power model for the aircraft engine;
modifying, by the one or more control devices, the baseline engine power model using the determined engine condition; and
determining, by the one or more control devices, an engine health factor based on the modified engine power model.
2. The method as claimed in claim 1, wherein the engine health factor is an engine torque factor.
3. The method as claimed in claim 2, wherein the engine condition includes a plurality of torque values of the aircraft engine determined during operation of the aircraft engine.
4. The method as claimed in claim 3, comprising
correcting, by the one or more control devices, the plurality of torque values of the aircraft engine determined during operation of the aircraft engine to a normalized condition.
5. The method as claimed in claim 4, wherein the baseline engine power model of the aircraft is an engine torque to turbine inlet temperature model defining a baseline engine line.
6. The method as claimed in claim 5, wherein modifying the baseline engine power model includes plotting, by the one or more control devices, the plurality of corrected torque values and updating, by the one or more control devices, the baseline

engine line to an updated engine line to reflect the plurality of corrected torque values.
7. The method as claimed in claim 6, wherein determining the engine torque factor based on the modified engine power model includes extrapolating, by the one or more control devices, a maximum engine torque available from the updated engine line.
8. The method as claimed in claim 1, comprising
determining, by the one or more control devices, a correction factor for the engine condition, and wherein modifying the baseline engine power model includes modifying, by the one or more control devices, the baseline engine power model using the determined engine condition and the correction factor.
9. A method for determining an engine heath factor of an aircraft engine
comprising:
determining, by one or more control devices, one or more engine limit factors during operation of the aircraft engine;
determining, by the one or more control devices, one or more ambient conditions;
correcting, by the one or more control devices, the one or more determined engine limit factors to a normalized condition;
determining, by the one or more control devices, a baseline engine health factor using the determined engine limit factors corrected to the normalized condition; and
modifying, by the one or more control devices, the determined baseline engine health factor to a real-time engine health factor based on the determined ambient conditions.
10. The method as claimed in claim 9, wherein the engine health factor is a
measure of power available.