diff --git a/core/src/net/sf/openrocket/file/rasaero/importt/SimulationListHandler.java b/core/src/net/sf/openrocket/file/rasaero/importt/SimulationListHandler.java
index 5d0547f79..194b63420 100644
--- a/core/src/net/sf/openrocket/file/rasaero/importt/SimulationListHandler.java
+++ b/core/src/net/sf/openrocket/file/rasaero/importt/SimulationListHandler.java
@@ -169,6 +169,9 @@ public class SimulationListHandler extends AbstractElementHandler {
 
         private void setSeparationDelay(final int stageNr, Double separationDelay,
                                         final FlightConfigurationId id) {
+            if (rocket.getStage(stageNr) == null) {
+                return;
+            }
             StageSeparationConfiguration config = rocket.getStage(stageNr).getSeparationConfigurations().get(id);
             if (separationDelay != null) {
                 config.setSeparationDelay(separationDelay);