diff --git a/pycontrails/core/aircraft_performance.py b/pycontrails/core/aircraft_performance.py
index b429648f..99bc1881 100644
--- a/pycontrails/core/aircraft_performance.py
+++ b/pycontrails/core/aircraft_performance.py
@@ -42,6 +42,13 @@ class AircraftPerformanceParams(ModelParams):
     #: the operational limits of the aircraft type.
     correct_fuel_flow: bool = True
 
+    #: Account for "in-service" engine deterioration between maintenance cycles.
+    #: Default value is set to +2.5% increase in fuel consumption.
+    # Reference:
+    # Gurrola Arrieta, M.D.J., Botez, R.M. and Lasne, A., 2024. An Engine Deterioration Model for
+    # Predicting Fuel Consumption Impact in a Regional Aircraft. Aerospace, 11(6), p.426.
+    engine_deterioration_factor: float = 0.025
+
     #: The number of iterations used to calculate aircraft mass and fuel flow.
     #: The default value of 3 is sufficient for most cases.
     n_iter: int = 3
diff --git a/pycontrails/models/ps_model/ps_model.py b/pycontrails/models/ps_model/ps_model.py
index f02b81ab..382d0cbc 100644
--- a/pycontrails/models/ps_model/ps_model.py
+++ b/pycontrails/models/ps_model/ps_model.py
@@ -51,13 +51,6 @@ class PSFlightParams(AircraftPerformanceParams):
     #: efficiency to always exceed this value.
     eta_over_eta_b_min: float | None = 0.5
 
-    #: Account for "in-service" engine deterioration between maintenance cycles.
-    #: Default value is set to +2.5% increase in fuel consumption.
-    # Reference:
-    # Gurrola Arrieta, M.D.J., Botez, R.M. and Lasne, A., 2024. An Engine Deterioration Model for
-    # Predicting Fuel Consumption Impact in a Regional Aircraft. Aerospace, 11(6), p.426.
-    engine_deterioration_factor: float = 0.025
-
 
 class PSFlight(AircraftPerformance):
     """Simulate aircraft performance using Poll-Schumann (PS) model.