introduce the runway definitions

src/airport/models/airport.model.ts

@@ -5,6 +5,7 @@ import { Constraint, ConstraintSchema } from './constraint.model';
 import { Planning, PlanningSchema } from './planning.model';
 import { RunwaySpacing, RunwaySpacingSchema } from './runwayspacing.model';
 import { Waypoint } from '../../generic/models/waypoint.model';
+import { Runway, RunwaySchema } from './runway.model';
 
 export type AirportDocument = Airport & Document;
 
@@ -29,6 +30,12 @@ export class Airport {
   })
   elevation: number;
 
+  @Prop({
+    required: true,
+    type: [RunwaySchema],
+  })
+  runways: Runway[];
+
   @Prop({
     type: [ConstraintSchema],
   })