fix a crash

aman/sys/Worker.py

@@ -106,7 +106,7 @@ class Worker(Thread):
                 for runway in self.SequencingConfiguration.ActiveArrivalRunways:
                     inbound = self.RecedingHorizonControl.lastFixedInboundOnRunway(runway.Runway.Name)
                     if None != inbound:
-                        preceedingInbounds[runway.Runway.Name] = inbound
+                        preceedingInbounds[runway.Runway.Name] = Node(inbound, None, None, None, None)
 
                 # configure the ACO run
                 acoConfig = Configuration(constraints = self.SequencingConfiguration, nav = self.Configuration.GngData,