diff --git a/core/src/net/sf/openrocket/optimization/rocketoptimization/domains/StabilityDomain.java b/core/src/net/sf/openrocket/optimization/rocketoptimization/domains/StabilityDomain.java
index e33f8189e..eab1c431d 100644
--- a/core/src/net/sf/openrocket/optimization/rocketoptimization/domains/StabilityDomain.java
+++ b/core/src/net/sf/openrocket/optimization/rocketoptimization/domains/StabilityDomain.java
@@ -63,7 +63,7 @@ public class StabilityDomain implements SimulationDomain {
 		 */
 		AerodynamicCalculator aerodynamicCalculator = new BarrowmanCalculator();
 		
-		FlightConfiguration configuration = simulation.getRocket().getSelectedConfiguration();
+		FlightConfiguration configuration = simulation.getActiveConfiguration();
 		FlightConditions conditions = new FlightConditions(configuration);
 		conditions.setMach(Application.getPreferences().getDefaultMach());
 		conditions.setAOA(0);
diff --git a/core/src/net/sf/openrocket/optimization/rocketoptimization/modifiers/FlightConfigurationModifier.java b/core/src/net/sf/openrocket/optimization/rocketoptimization/modifiers/FlightConfigurationModifier.java
index 21f32da6c..4ca45b337 100644
--- a/core/src/net/sf/openrocket/optimization/rocketoptimization/modifiers/FlightConfigurationModifier.java
+++ b/core/src/net/sf/openrocket/optimization/rocketoptimization/modifiers/FlightConfigurationModifier.java
@@ -71,7 +71,7 @@ public class FlightConfigurationModifier<E extends FlightConfigurableParameter<E
 		}
 		
 		FlightConfigurableParameterSet<E> configSet = (FlightConfigurableParameterSet<E>) configGetter.invoke(c);
-		return configSet.get(simulation.getRocket().getSelectedConfiguration().getFlightConfigurationID());
+		return configSet.get(simulation.getFlightConfigurationId());
 	}
 	
 }
diff --git a/swing/src/net/sf/openrocket/gui/simulation/SimulationRunDialog.java b/swing/src/net/sf/openrocket/gui/simulation/SimulationRunDialog.java
index 077112d8c..5fb8402a7 100644
--- a/swing/src/net/sf/openrocket/gui/simulation/SimulationRunDialog.java
+++ b/swing/src/net/sf/openrocket/gui/simulation/SimulationRunDialog.java
@@ -292,7 +292,7 @@ public class SimulationRunDialog extends JDialog {
 			double otherBurn = 0;
 			
 			
-			FlightConfiguration config = simulation.getRocket().getSelectedConfiguration();
+			FlightConfiguration config = simulation.getActiveConfiguration();
 			Collection<MotorConfiguration> activeMotors = config.getActiveMotors();
 			
 			for (MotorConfiguration curInstance : activeMotors) {