diff --git a/src/FirmwarePlugin/APM/APMFirmwarePlugin.cc b/src/FirmwarePlugin/APM/APMFirmwarePlugin.cc
index 188e7f62d42571caa4da6372c30b0c57e760b422..f4a0015ce9f469c804240a42d69b1d39290967b4 100644
--- a/src/FirmwarePlugin/APM/APMFirmwarePlugin.cc
+++ b/src/FirmwarePlugin/APM/APMFirmwarePlugin.cc
@@ -313,7 +313,7 @@ bool APMFirmwarePlugin::_handleStatusText(Vehicle* vehicle, mavlink_message_t* m
     mavlink_statustext_t statusText;
     mavlink_msg_statustext_decode(message, &statusText);
 
-    if (vehicle->firmwareMajorVersion() == -1 || statusText.severity < MAV_SEVERITY_NOTICE) {
+    if (vehicle->firmwareMajorVersion() == Vehicle::versionNotSetValue || statusText.severity < MAV_SEVERITY_NOTICE) {
         messageText = _getMessageText(message);
         qCDebug(APMFirmwarePluginLog) << messageText;
 
diff --git a/src/Vehicle/Vehicle.cc b/src/Vehicle/Vehicle.cc
index 0994aa23af070dd4ff57822db47679cd3ff33c58..594a80ee7d99c1bd23691eb0d1caea77129fdc69 100644
--- a/src/Vehicle/Vehicle.cc
+++ b/src/Vehicle/Vehicle.cc
@@ -121,9 +121,9 @@ Vehicle::Vehicle(LinkInterface*             link,
     , _messageSeq(0)
     , _compID(0)
     , _heardFrom(false)
-    , _firmwareMajorVersion(-1)
-    , _firmwareMinorVersion(-1)
-    , _firmwarePatchVersion(-1)
+    , _firmwareMajorVersion(versionNotSetValue)
+    , _firmwareMinorVersion(versionNotSetValue)
+    , _firmwarePatchVersion(versionNotSetValue)
     , _rollFact             (0, _rollFactName,              FactMetaData::valueTypeDouble)
     , _pitchFact            (0, _pitchFactName,             FactMetaData::valueTypeDouble)
     , _headingFact          (0, _headingFactName,           FactMetaData::valueTypeDouble)
@@ -291,9 +291,9 @@ Vehicle::Vehicle(QObject* parent)
     , _messageSeq(0)
     , _compID(0)
     , _heardFrom(false)
-    , _firmwareMajorVersion(-1)
-    , _firmwareMinorVersion(-1)
-    , _firmwarePatchVersion(-1)
+    , _firmwareMajorVersion(versionNotSetValue)
+    , _firmwareMinorVersion(versionNotSetValue)
+    , _firmwarePatchVersion(versionNotSetValue)
     , _rollFact             (0, _rollFactName,              FactMetaData::valueTypeDouble)
     , _pitchFact            (0, _pitchFactName,             FactMetaData::valueTypeDouble)
     , _headingFact          (0, _headingFactName,           FactMetaData::valueTypeDouble)
diff --git a/src/Vehicle/Vehicle.h b/src/Vehicle/Vehicle.h
index a739c6f4ef06906c25a8a61f92dd2e8f4c8b6918..8880214a45a6f692d872d73ec0636cc096d23551 100644
--- a/src/Vehicle/Vehicle.h
+++ b/src/Vehicle/Vehicle.h
@@ -524,6 +524,7 @@ public:
     int firmwareMinorVersion(void) const { return _firmwareMinorVersion; }
     int firmwarePatchVersion(void) const { return _firmwarePatchVersion; }
     void setFirmwareVersion(int majorVersion, int minorVersion, int patchVersion);
+    static const int versionNotSetValue = -1;
 
 public slots:
     void setLatitude(double latitude);