diff --git a/src/blackcore/afv/clients/afvclient.cpp b/src/blackcore/afv/clients/afvclient.cpp
index b6b6e4f2d0..6a310dbaaa 100644
--- a/src/blackcore/afv/clients/afvclient.cpp
+++ b/src/blackcore/afv/clients/afvclient.cpp
@@ -183,7 +183,7 @@ namespace BlackCore::Afv::Clients
             m_connection->connectTo(cid, password, callsign, client,
                                     { // this is the callback when the connection has been established
                                       this, [=](bool authenticated) {
-                                          if (!myself) { return; }
+                                          if (!myself) { return; } // cppcheck-suppress knownConditionTrueFalse
 
                                           // HF stations aliased
                                           const QVector<StationDto> aliasedStations = m_connection->getAllAliasedStations();
diff --git a/src/blackcore/afv/connection/apiserverconnection.cpp b/src/blackcore/afv/connection/apiserverconnection.cpp
index 4d6b979df3..7506c702b3 100644
--- a/src/blackcore/afv/connection/apiserverconnection.cpp
+++ b/src/blackcore/afv/connection/apiserverconnection.cpp
@@ -69,7 +69,7 @@ namespace BlackCore::Afv::Connection
                             { this, [=](QNetworkReply *nwReply) {
                                  // called in "this" thread
                                  const QScopedPointer<QNetworkReply, QScopedPointerDeleteLater> reply(nwReply);
-                                 if (!myself || isShuttingDown()) { return; }
+                                 if (!myself || isShuttingDown()) { return; } // cppcheck-suppress knownConditionTrueFalse
 
                                  this->logRequestDuration(reply.data(), "authentication");
                                  if (reply->error() != QNetworkReply::NoError)
@@ -278,7 +278,7 @@ namespace BlackCore::Afv::Connection
             QPointer<CApiServerConnection> myself(this);
             this->connectTo(m_username, m_password, m_client, m_networkVersion,
                             { this, [=](bool authenticated) {
-                                 if (!myself) { return; }
+                                 if (!myself) { return; } // cppcheck-suppress knownConditionTrueFalse
                                  CLogMessage(this).info(u"API server authenticated '%1': %2") << m_username << boolToYesNo(authenticated);
                              } });
         }
diff --git a/src/blackcore/afv/connection/clientconnection.cpp b/src/blackcore/afv/connection/clientconnection.cpp
index fe6fc4f102..6babce7ced 100644
--- a/src/blackcore/afv/connection/clientconnection.cpp
+++ b/src/blackcore/afv/connection/clientconnection.cpp
@@ -50,7 +50,7 @@ namespace BlackCore::Afv::Connection
                                          { // callback called when connected
                                            this, [=](bool authenticated) {
                                                // callback when connection has been established
-                                               if (!myself) { return; }
+                                               if (!myself) { return; } // cppcheck-suppress knownConditionTrueFalse
 
                                                if (authenticated)
                                                {
diff --git a/src/blackcore/afv/model/afvmapreader.cpp b/src/blackcore/afv/model/afvmapreader.cpp
index 99f14fd944..345d35878e 100644
--- a/src/blackcore/afv/model/afvmapreader.cpp
+++ b/src/blackcore/afv/model/afvmapreader.cpp
@@ -32,7 +32,7 @@ namespace BlackCore::Afv::Model
         {
             loop.exec();
         }
-        const QByteArray jsonData = reply->readAll();
+        const QByteArray jsonData = reply ? reply->readAll() : QByteArray {};
         if (reply) { reply->deleteLater(); }
 
         if (jsonData.isEmpty()) { return; }
diff --git a/src/blackcore/airspacemonitor.cpp b/src/blackcore/airspacemonitor.cpp
index 3e6cad6052..7e6a9ce909 100644
--- a/src/blackcore/airspacemonitor.cpp
+++ b/src/blackcore/airspacemonitor.cpp
@@ -186,7 +186,7 @@ namespace BlackCore
             eventLoop.stopWhen(m_fsdClient, &CFSDClient::flightPlanReceived, [=](const auto &cs, const auto &) { return cs == callsign; });
             if (eventLoop.exec(1500))
             {
-                if (!myself || !sApp || sApp->isShuttingDown()) { return CFlightPlan(); }
+                if (!myself || !sApp || sApp->isShuttingDown()) { return CFlightPlan(); } // cppcheck-suppress knownConditionTrueFalse
                 if (m_flightPlanCache.contains(callsign))
                 {
                     plan = m_flightPlanCache[callsign];
diff --git a/src/blackcore/context/contextsimulatorimpl.cpp b/src/blackcore/context/contextsimulatorimpl.cpp
index a5362496c4..06969aaa71 100644
--- a/src/blackcore/context/contextsimulatorimpl.cpp
+++ b/src/blackcore/context/contextsimulatorimpl.cpp
@@ -644,7 +644,7 @@ namespace BlackCore::Context
         if (!m_simulatorPlugin.first.isUnspecified())
         {
             ISimulator *simulator = m_simulatorPlugin.second;
-            if (simulator->isConnected())
+            if (simulator && simulator->isConnected())
             {
                 // we are about to unload an connected simulator
                 this->updateMarkAllAsNotRendered(); // without plugin nothing can be rendered
diff --git a/src/blackcore/setupreader.cpp b/src/blackcore/setupreader.cpp
index b68db6254d..37d8303fa2 100644
--- a/src/blackcore/setupreader.cpp
+++ b/src/blackcore/setupreader.cpp
@@ -117,7 +117,7 @@ namespace BlackCore
                     // "retry" possible in some cases
                     do
                     {
-                        if (ignoreCmdBootstrapUrl || !checkCmdBootstrapUrl || CNetworkUtils::canConnect(url, CNetworkUtils::getLongTimeoutMs()))
+                        if (ignoreCmdBootstrapUrl || !checkCmdBootstrapUrl || CNetworkUtils::canConnect(url, CNetworkUtils::getLongTimeoutMs())) // cppcheck-suppress knownConditionTrueFalse
                         {
                             ok = true;
                             break;
@@ -308,7 +308,6 @@ namespace BlackCore
     {
         Q_ASSERT_X(!(webRead && localRead), Q_FUNC_INFO, "Local and web read together seems to be wrong");
         CStatusMessageList msgs;
-        QPointer<CSetupReader> myself(this);
 
         bool available = false;
         if (webRead || localRead)
diff --git a/src/blackgui/components/settingsnetworkserverscomponent.cpp b/src/blackgui/components/settingsnetworkserverscomponent.cpp
index a41c644f5e..b6addb327d 100644
--- a/src/blackgui/components/settingsnetworkserverscomponent.cpp
+++ b/src/blackgui/components/settingsnetworkserverscomponent.cpp
@@ -98,7 +98,6 @@ namespace BlackGui::Components
         else
         {
             qFatal("Wrong sender");
-            // cppcheck-suppress duplicateBreak
             return;
         }
 
diff --git a/src/blackgui/loadindicator.cpp b/src/blackgui/loadindicator.cpp
index 32b8010989..41018e63b7 100644
--- a/src/blackgui/loadindicator.cpp
+++ b/src/blackgui/loadindicator.cpp
@@ -62,7 +62,7 @@ namespace BlackGui
         if (processEvents && sGui)
         {
             sGui->processEventsToRefreshGui();
-            if (!myself) { return -1; } // deleted in meantime (process events)
+            if (!myself) { return -1; } // cppcheck-suppress knownConditionTrueFalse // deleted in meantime (process events)
         }
 
         const int stopId = m_currentId++; // copy
diff --git a/src/blackgui/menus/menuaction.cpp b/src/blackgui/menus/menuaction.cpp
index b5134212d1..3725d6367f 100644
--- a/src/blackgui/menus/menuaction.cpp
+++ b/src/blackgui/menus/menuaction.cpp
@@ -534,7 +534,11 @@ namespace BlackGui::Menus
         }
         Q_ASSERT_X(subMenu, Q_FUNC_INFO, "Could not create sub menu");
 
-        subMenu->setParent(parentMenu);
+        if (subMenu)
+        {
+            subMenu->setParent(parentMenu);
+        }
+
         if (pathDepth > 0 && subMenu)
         {
             subMenus.insert(key, subMenu);
diff --git a/src/blackgui/views/viewbase.cpp b/src/blackgui/views/viewbase.cpp
index 79a79f13c6..d26ea0ea21 100644
--- a/src/blackgui/views/viewbase.cpp
+++ b/src/blackgui/views/viewbase.cpp
@@ -75,7 +75,7 @@ namespace BlackGui::Views
         const int c = m_model->update(container, sort);
 
         // resize after real update according to mode
-        if (presizeThresholdReached)
+        if (presizeThresholdReached) // cppcheck-suppress knownConditionTrueFalse
         {
             // currently no furhter actions
         }
@@ -83,7 +83,7 @@ namespace BlackGui::Views
         {
             this->resizeToContents(); // mode based resize
         }
-        else if (presize && !presizeThresholdReached)
+        else if (presize && !presizeThresholdReached) // cppcheck-suppress knownConditionTrueFalse
         {
             // small amount of data not covered before
             this->fullResizeToContents();
diff --git a/src/blackinput/win/keyboardwindows.cpp b/src/blackinput/win/keyboardwindows.cpp
index d6c7645821..747be9f2e7 100644
--- a/src/blackinput/win/keyboardwindows.cpp
+++ b/src/blackinput/win/keyboardwindows.cpp
@@ -143,8 +143,7 @@ namespace BlackInput
 
     bool CKeyboardWindows::init()
     {
-        // cppcheck-suppress knownConditionTrueFalse
-        if (useWindowsHook)
+        if (useWindowsHook) // cppcheck-suppress knownConditionTrueFalse
         {
             Q_ASSERT_X(g_keyboardWindows == nullptr, "CKeyboardWindows::init", "Windows supports only one keyboard instance. Cannot initialize a second one!");
             g_keyboardWindows = this;
diff --git a/src/blackmisc/aviation/aircraftsituation.cpp b/src/blackmisc/aviation/aircraftsituation.cpp
index 8601d180fe..0e8db5edac 100644
--- a/src/blackmisc/aviation/aircraftsituation.cpp
+++ b/src/blackmisc/aviation/aircraftsituation.cpp
@@ -52,18 +52,18 @@ namespace BlackMisc::Aviation
             lights.setBeaconOn(true);
             lights.setNavOn(true);
 
-            if (gsKts > 5)
-            {
-                // mode taxi
-                lights.setTaxiOn(true);
-                lights.setLandingOn(false);
-            }
-            else if (gsKts > 30)
+            if (gsKts > 30)
             {
                 // mode accelaration for takeoff
                 lights.setTaxiOn(false);
                 lights.setLandingOn(true);
             }
+            else if (gsKts > 5)
+            {
+                // mode taxi
+                lights.setTaxiOn(true);
+                lights.setLandingOn(false);
+            }
             else
             {
                 // slow movements or parking
diff --git a/src/blackmisc/aviation/flightplan.cpp b/src/blackmisc/aviation/flightplan.cpp
index a75e97fa70..a77f08fffa 100644
--- a/src/blackmisc/aviation/flightplan.cpp
+++ b/src/blackmisc/aviation/flightplan.cpp
@@ -748,7 +748,7 @@ namespace BlackMisc::Aviation
         if (firstSplit.size() >= 2)
         {
             // format like B789/H-SDE1E2E3FGHIJ2J3J4J5M1RWXY/LB1D1
-            QString equipment = firstSplit.size() >= 2 ? firstSplit[1] : "";
+            QString equipment = firstSplit[1];
             QStringList split = firstSplit[0].split('/');
             if (split.size() >= 3)
             {
diff --git a/src/blackmisc/aviation/selcal.cpp b/src/blackmisc/aviation/selcal.cpp
index 96f46cd91b..4b2addae3a 100644
--- a/src/blackmisc/aviation/selcal.cpp
+++ b/src/blackmisc/aviation/selcal.cpp
@@ -74,7 +74,7 @@ namespace BlackMisc::Aviation
         if ((p3 = CSelcal::validCharacters().indexOf(codeUpper.at(2))) < 0) return false;
         if ((p4 = CSelcal::validCharacters().indexOf(codeUpper.at(3))) < 0) return false;
         if (p1 >= p2 || p3 >= p4) return false; // pair in alphabetical order
-        if (p1 == p3 || p2 == p3 || p2 == p4 || p3 == p4) return false; // given letter can be used only once in a SELCAL code
+        if (p1 == p3 || p2 == p3 || p2 == p4 || p3 == p4) return false; // cppcheck-suppress knownConditionTrueFalse // given letter can be used only once in a SELCAL code
         return true;
     }
 
diff --git a/src/blackmisc/datacache.cpp b/src/blackmisc/datacache.cpp
index 60ecc6d229..e46d709ff8 100644
--- a/src/blackmisc/datacache.cpp
+++ b/src/blackmisc/datacache.cpp
@@ -352,7 +352,7 @@ namespace BlackMisc
     class BLACKMISC_EXPORT CDataCacheRevision::Session
     {
     public:
-        // cppcheck-suppress unusedFunction
+        // cppcheck-suppress missingReturn
         Session(const QString &filename) : m_filename(filename) {}
         void updateSession();
         const QUuid &uuid() const { return m_uuid; }
diff --git a/src/blackmisc/dbusserver.cpp b/src/blackmisc/dbusserver.cpp
index 92056c6536..81726dc3b6 100644
--- a/src/blackmisc/dbusserver.cpp
+++ b/src/blackmisc/dbusserver.cpp
@@ -380,8 +380,7 @@ namespace BlackMisc
         QString p = port.toLower().trimmed();
         if (!p.isEmpty())
         {
-            // cppcheck-suppress ignoredReturnValue
-            p.toShort(&ok);
+            p.toShort(&ok); // cppcheck-suppress ignoredReturnValue
             if (!ok)
             {
                 p = ""; // was not a number
diff --git a/src/blackmisc/fileutils.cpp b/src/blackmisc/fileutils.cpp
index 350a9ce0d7..14bd9a1340 100644
--- a/src/blackmisc/fileutils.cpp
+++ b/src/blackmisc/fileutils.cpp
@@ -64,7 +64,7 @@ namespace BlackMisc
     bool CFileUtils::writeStringToLockedFile(const QString &content, const QString &fileNameAndPath)
     {
         QLockFile lock(fileNameAndPath + ".lock");
-        lock.lock();
+        if (!lock.lock()) { return false; }
         return writeStringToFile(content, fileNameAndPath);
     }
 
@@ -81,7 +81,7 @@ namespace BlackMisc
     QString CFileUtils::readLockedFileToString(const QString &fileNameAndPath)
     {
         QLockFile lock(fileNameAndPath + ".lock");
-        lock.lock();
+        if (!lock.lock()) { return {}; }
         return readFileToString(fileNameAndPath);
     }
 
diff --git a/src/blackmisc/mixin/mixinjson.h b/src/blackmisc/mixin/mixinjson.h
index c66174fe92..5bb7969d76 100644
--- a/src/blackmisc/mixin/mixinjson.h
+++ b/src/blackmisc/mixin/mixinjson.h
@@ -161,10 +161,9 @@ namespace BlackMisc
                     if (value.isUndefined())
                     {
                         constexpr bool required = false; //! \fixme add RequiredForJson flag in metaclass system
-                        // cppcheck-suppress knownConditionTrueFalse
                         // QLatin1String used instead of QStringLiteral below since the latter causes an internal compiler bug
                         // in GCC 8 and higher
-                        if (required) { throw CJsonException(QLatin1String("Missing required member '%1'").arg(member.latin1Name())); }
+                        if (required) { throw CJsonException(QLatin1String("Missing required member '%1'").arg(member.latin1Name())); } // cppcheck-suppress knownConditionTrueFalse
                     }
                     else
                     {
diff --git a/src/blackmisc/simplecommandparser.cpp b/src/blackmisc/simplecommandparser.cpp
index 0ea035b70b..fe06e419e2 100644
--- a/src/blackmisc/simplecommandparser.cpp
+++ b/src/blackmisc/simplecommandparser.cpp
@@ -86,8 +86,7 @@ namespace BlackMisc
         const QString p = this->part(index);
         if (p.isEmpty()) { return false; }
         bool ok = false;
-        // cppcheck-suppress ignoredReturnValue
-        p.toInt(&ok);
+        p.toInt(&ok); // cppcheck-suppress ignoredReturnValue
         return ok;
     }
 
diff --git a/src/blackmisc/simulation/aircraftmodellist.cpp b/src/blackmisc/simulation/aircraftmodellist.cpp
index 2f4a8ae235..be19152c24 100644
--- a/src/blackmisc/simulation/aircraftmodellist.cpp
+++ b/src/blackmisc/simulation/aircraftmodellist.cpp
@@ -1030,14 +1030,11 @@ namespace BlackMisc::Simulation
         }
         const QMultiMap<int, CSimulatorInfo> cps(counts.countPerSimulator());
         CSimulatorInfo maxSim = cps.last();
-        if (simulatorsRepresented > 0)
+        const int count = cps.lastKey(); // how many elements
+        const QList<CSimulatorInfo> infoWithMaxValues = cps.values(count); // all with the same counts
+        for (const CSimulatorInfo &info : infoWithMaxValues)
         {
-            const int count = cps.lastKey(); // how many elements
-            const QList<CSimulatorInfo> infoWithMaxValues = cps.values(count); // all with the same counts
-            for (const CSimulatorInfo &info : infoWithMaxValues)
-            {
-                maxSim.addSimulator(info);
-            }
+            maxSim.addSimulator(info);
         }
         return maxSim;
     }
diff --git a/src/blackmisc/simulation/fscommon/vpilotrulesreader.cpp b/src/blackmisc/simulation/fscommon/vpilotrulesreader.cpp
index 45f6866fd5..4cbd2ccc5a 100644
--- a/src/blackmisc/simulation/fscommon/vpilotrulesreader.cpp
+++ b/src/blackmisc/simulation/fscommon/vpilotrulesreader.cpp
@@ -148,7 +148,7 @@ namespace BlackMisc::Simulation::FsCommon
             if (m_shutdown) { return false; }
             loadedFiles++;
             bool s = this->loadFile(fn, rules);
-            if (!s) { this->m_fileListWithProblems.append(fn); }
+            if (!s) { filesWithProblems.append(fn); }
         }
 
         {
diff --git a/src/plugins/simulator/fscommon/fsuipcimpl.cpp b/src/plugins/simulator/fscommon/fsuipcimpl.cpp
index 5f13a67284..4612c334d8 100644
--- a/src/plugins/simulator/fscommon/fsuipcimpl.cpp
+++ b/src/plugins/simulator/fscommon/fsuipcimpl.cpp
@@ -498,8 +498,7 @@ namespace BlackSimPlugin::FsCommon
                 // position
                 const double latCorrectionFactor = 90.0 / (10001750.0 * 65536.0 * 65536.0);
                 const double lonCorrectionFactor = 360.0 / (65536.0 * 65536.0 * 65536.0 * 65536.0);
-                // cppcheck-suppress shadowArgument
-                CAircraftSituation situation = aircraft.getSituation();
+                CAircraftSituation situation = aircraft.getSituation(); // cppcheck-suppress shadowArgument
                 CCoordinateGeodetic position = situation.getPosition();
                 CLatitude lat(latitudeRaw * latCorrectionFactor, CAngleUnit::deg());
                 CLongitude lon(longitudeRaw * lonCorrectionFactor, CAngleUnit::deg());
diff --git a/src/plugins/simulator/fsxcommon/simulatorfsxcommon.cpp b/src/plugins/simulator/fsxcommon/simulatorfsxcommon.cpp
index 1f18302000..b50a1a4d63 100644
--- a/src/plugins/simulator/fsxcommon/simulatorfsxcommon.cpp
+++ b/src/plugins/simulator/fsxcommon/simulatorfsxcommon.cpp
@@ -1214,7 +1214,7 @@ namespace BlackSimPlugin::FsxCommon
             verified = true;
         }
 
-        if (!verified)
+        if (!verified) // cppcheck-suppress knownConditionTrueFalse
         {
             CLogMessage(this).info(u"Disable probes: '%1' failed to relase control") << cs.asString();
             m_useFsxTerrainProbe = false;
@@ -2641,8 +2641,7 @@ namespace BlackSimPlugin::FsxCommon
     void CSimulatorFsxCommon::traceSendId(const CSimConnectObject &simObject, const QString &functionName, const QString &details, bool forceTrace)
     {
         if (!forceTrace && !this->isTracingSendId()) { return; }
-        // cppcheck-suppress knownConditionTrueFalse
-        if (MaxSendIdTraces < 1) { return; }
+        if (MaxSendIdTraces < 1) { return; } // cppcheck-suppress knownConditionTrueFalse
         DWORD dwLastId = 0;
         const HRESULT hr = SimConnect_GetLastSentPacketID(m_hSimConnect, &dwLastId);
         if (isFailure(hr)) { return; }
diff --git a/src/xswiftbus/dbusdispatcher.cpp b/src/xswiftbus/dbusdispatcher.cpp
index 035c7de08d..16db3ef29c 100644
--- a/src/xswiftbus/dbusdispatcher.cpp
+++ b/src/xswiftbus/dbusdispatcher.cpp
@@ -190,7 +190,7 @@ namespace XSwiftBus
         return true;
     }
 
-    void CDBusDispatcher::dbusRemoveWatch(DBusWatch *watch)
+    void CDBusDispatcher::dbusRemoveWatch(const DBusWatch *watch)
     {
         for (auto it = m_watchers.begin(); it != m_watchers.end();)
         {
diff --git a/src/xswiftbus/dbusdispatcher.h b/src/xswiftbus/dbusdispatcher.h
index 9115bae797..4336c6c8f3 100644
--- a/src/xswiftbus/dbusdispatcher.h
+++ b/src/xswiftbus/dbusdispatcher.h
@@ -83,7 +83,7 @@ namespace XSwiftBus
         void dispatch();
 
         dbus_bool_t dbusAddWatch(DBusWatch *watch);
-        void dbusRemoveWatch(DBusWatch *watch);
+        void dbusRemoveWatch(const DBusWatch *watch);
         void dbusWatchToggled(DBusWatch *watch);
 
         dbus_bool_t dbusAddTimeout(DBusTimeout *timeout);
diff --git a/src/xswiftbus/menus.cpp b/src/xswiftbus/menus.cpp
index 5f99dd459f..e019e526c5 100644
--- a/src/xswiftbus/menus.cpp
+++ b/src/xswiftbus/menus.cpp
@@ -103,6 +103,7 @@ namespace XSwiftBus
         return { XPLMCreateMenu(name.c_str(), m_data->id, XPLMAppendMenuItem(m_data->id, name.c_str(), nullptr, false), handler, itemsVoidPtr), false, std::move(items) };
     }
 
+    // cppcheck-suppress constParameter
     void CMenu::handler(void *menuRef, void *itemRef)
     {
         if (menuRef && itemRef)
diff --git a/src/xswiftbus/traffic.cpp b/src/xswiftbus/traffic.cpp
index fd3e858103..ddbbcfbf11 100644
--- a/src/xswiftbus/traffic.cpp
+++ b/src/xswiftbus/traffic.cpp
@@ -980,8 +980,7 @@ namespace XSwiftBus
             int h = top - bottom;
             x -= left;
             y -= bottom;
-            // cppcheck-suppress knownConditionTrueFalse
-            if (DEBUG) { DEBUG_LOG("Follow aircraft coordinates w,h,x,y: " + std::to_string(w) + " " + std::to_string(h) + " " + std::to_string(x) + " " + std::to_string(y)); }
+            if (DEBUG) { DEBUG_LOG("Follow aircraft coordinates w,h,x,y: " + std::to_string(w) + " " + std::to_string(h) + " " + std::to_string(x) + " " + std::to_string(y)); } // cppcheck-suppress knownConditionTrueFalse
             if (traffic->m_lastMouseX == x && traffic->m_lastMouseY == y && traffic->m_lastMouseX >= 0 && traffic->m_lastMouseY >= 0)
             {
                 // mouse NOT moving, we lost focus or we do NOT move anymore
@@ -1099,8 +1098,7 @@ namespace XSwiftBus
             return 0;
         }
 
-        // cppcheck-suppress knownConditionTrueFalse
-        if (DEBUG)
+        if (DEBUG) // cppcheck-suppress knownConditionTrueFalse
         {
             DEBUG_LOG("Camera: " + pos2String(cameraPosition));
             DEBUG_LOG("Follow aircraft " + traffic->m_followPlaneViewCallsign + " " + modelName);