diff --git a/src/Airports/airport.hxx b/src/Airports/airport.hxx
index fb27e4369..b4f87e98d 100644
--- a/src/Airports/airport.hxx
+++ b/src/Airports/airport.hxx
@@ -32,6 +32,7 @@
 #include <string>
 #include <vector>
 #include <map>
+#include <memory>
 
 #include <Navaids/positioned.hxx>
 #include <Navaids/procedure.hxx>