diff --git a/src/modules/vtol_att_control/vtol_att_control_main.cpp b/src/modules/vtol_att_control/vtol_att_control_main.cpp
index 44631343c4..9ad050645e 100644
--- a/src/modules/vtol_att_control/vtol_att_control_main.cpp
+++ b/src/modules/vtol_att_control/vtol_att_control_main.cpp
@@ -177,6 +177,11 @@ VtolAttitudeControl::~VtolAttitudeControl()
 		} while (_control_task != -1);
 	}
 
+	// free memory used by instances of base class VtolType
+	if (_vtol_type != nullptr) {
+		delete _vtol_type;
+	}
+
 	VTOL_att_control::g_control = nullptr;
 }
 
diff --git a/src/modules/vtol_att_control/vtol_att_control_main.h b/src/modules/vtol_att_control/vtol_att_control_main.h
index 1f0917f12f..e268a92b20 100644
--- a/src/modules/vtol_att_control/vtol_att_control_main.h
+++ b/src/modules/vtol_att_control/vtol_att_control_main.h
@@ -218,10 +218,10 @@ private:
 	int _transition_command;
 	bool _abort_front_transition;
 
-	VtolType *_vtol_type;	// base class for different vtol types
-	Tiltrotor *_tiltrotor;	// tailsitter vtol type
-	Tailsitter *_tailsitter;	// tiltrotor vtol type
-	Standard *_standard;	// standard vtol type
+	VtolType *_vtol_type = nullptr;	// base class for different vtol types
+	Tiltrotor *_tiltrotor = nullptr;	// tailsitter vtol type
+	Tailsitter *_tailsitter = nullptr;	// tiltrotor vtol type
+	Standard *_standard = nullptr;	// standard vtol type
 
 //*****************Member functions***********************************************************************