diff --git a/simgear/misc/interpolator.hxx b/simgear/misc/interpolator.hxx
index 17f72474..df530ee8 100644
--- a/simgear/misc/interpolator.hxx
+++ b/simgear/misc/interpolator.hxx
@@ -38,6 +38,9 @@ public:
     // Subsystem API.
     void update(double delta_time_sec) override;
 
+    // Subsystem identification.
+    static const char* staticSubsystemClassId() { return "interpolator"; }
+
     // Simple method that interpolates a double property value from
     // its current value (default of zero) to the specified target
     // over the specified time.
diff --git a/simgear/scene/tsync/terrasync.hxx b/simgear/scene/tsync/terrasync.hxx
index 89400f04..4d4c0e39 100644
--- a/simgear/scene/tsync/terrasync.hxx
+++ b/simgear/scene/tsync/terrasync.hxx
@@ -50,6 +50,9 @@ public:
     void unbind() override;
     void update(double) override;
 
+    // Subsystem identification.
+    static const char* staticSubsystemClassId() { return "terrasync"; }
+
     /// notify terrasync that the sim was repositioned, as opposed to
     /// us travelling in a direction. Avoid last_lat / last_lon blocking
     /// certain tiles when we reposition.
diff --git a/simgear/structure/SGPerfMon.hxx b/simgear/structure/SGPerfMon.hxx
index 14745cd2..63354d4a 100644
--- a/simgear/structure/SGPerfMon.hxx
+++ b/simgear/structure/SGPerfMon.hxx
@@ -43,6 +43,9 @@ public:
     void unbind() override;
     void update(double dt) override;
 
+    // Subsystem identification.
+    static const char* staticSubsystemClassId() { return "performance-mon"; }
+
 private:
     static void subSystemMgrHook(void* userData, const std::string& name, SampleStatistic* timeStat);
 
diff --git a/simgear/structure/event_mgr.hxx b/simgear/structure/event_mgr.hxx
index caf860b0..9873cf71 100644
--- a/simgear/structure/event_mgr.hxx
+++ b/simgear/structure/event_mgr.hxx
@@ -82,6 +82,9 @@ public:
     void unbind() override;
     void update(double delta_time_sec) override;
 
+    // Subsystem identification.
+    static const char* staticSubsystemClassId() { return "events"; }
+
     void setRealtimeProperty(SGPropertyNode* node) { _rtProp = node; }
 
     /**
diff --git a/simgear/structure/subsystem_mgr.hxx b/simgear/structure/subsystem_mgr.hxx
index af91dd4d..938bdb23 100644
--- a/simgear/structure/subsystem_mgr.hxx
+++ b/simgear/structure/subsystem_mgr.hxx
@@ -525,6 +525,9 @@ public:
     void update(double delta_time_sec) override;
     bool is_suspended() const override;
 
+    // Subsystem identification.
+    static const char* staticSubsystemClassId() { return "subsystem-mgr"; }
+
     virtual void add (const char * name,
                       SGSubsystem * subsystem,
                       GroupType group = GENERAL,