diff --git a/src/Replay/replay.cxx b/src/Replay/replay.cxx
index d0dc3f6fa..9b8a44760 100644
--- a/src/Replay/replay.cxx
+++ b/src/Replay/replay.cxx
@@ -31,6 +31,13 @@
 
 #include "replay.hxx"
 
+const double FGReplay::st_list_time = 60.0;   // 60 secs of high res data
+const double FGReplay::mt_list_time = 600.0;  // 10 mins of 1 fps data
+const double FGReplay::lt_list_time = 3600.0; // 1 hr of 10 spf data
+
+// short term sample rate is as every frame
+const double FGReplay::mt_dt = 0.5; // medium term sample rate (sec)
+const double FGReplay::lt_dt = 5.0; // long term sample rate (sec)
 
 /**
  * Constructor
diff --git a/src/Replay/replay.hxx b/src/Replay/replay.hxx
index f9ab649a2..41f1a4a62 100644
--- a/src/Replay/replay.hxx
+++ b/src/Replay/replay.hxx
@@ -79,13 +79,13 @@ public:
     
 private:
 
-    static const double st_list_time = 60.0;   // 60 secs of high res data
-    static const double mt_list_time = 600.0;  // 10 mins of 1 fps data
-    static const double lt_list_time = 3600.0; // 1 hr of 10 spf data
+    static const double st_list_time;   // 60 secs of high res data
+    static const double mt_list_time;  // 10 mins of 1 fps data
+    static const double lt_list_time; // 1 hr of 10 spf data
 
     // short term sample rate is as every frame
-    static const double mt_dt = 0.5; // medium term sample rate (sec)
-    static const double lt_dt = 5.0; // long term sample rate (sec)
+    static const double mt_dt; // medium term sample rate (sec)
+    static const double lt_dt; // long term sample rate (sec)
 
     double sim_time;
     double last_mt_time;