diff --git a/samples/blackmisc/samplesperformance.cpp b/samples/blackmisc/samplesperformance.cpp
index 86fb443f8..7bdeb32ab 100644
--- a/samples/blackmisc/samplesperformance.cpp
+++ b/samples/blackmisc/samplesperformance.cpp
@@ -186,6 +186,18 @@ namespace BlackMiscTest
         }
         out << "Reads by callsigns: " << timer.elapsed() << "ms" << endl;
 
+        timer.start();
+        for (int i = 0; i < 10; i++)
+        {
+            QMap<CCallsign, CAircraftSituationList> splitList = situations.splitPerCallsign();
+            Q_ASSERT(splitList.size() == numberOfCallsigns);
+            for (const CAircraftSituationList &slcs : splitList.values())
+            {
+                Q_ASSERT(slcs.size() == numberOfTimes);
+            }
+        }
+        out << "Reads by callsigns split: " << timer.elapsed() << "ms" << endl;
+
         timer.start();
         for (int i = 0; i < 10; i++)
         {
@@ -204,9 +216,10 @@ namespace BlackMiscTest
             {
                 CCallsign callsign("CS" + QString::number(cs));
                 CAircraftSituationList r = situations.findByCallsign(callsign).findBefore(baseTimeEpoch + 1 + (10 * t));
+                Q_UNUSED(r);
             }
         }
-        out << "Reads by callsign / times: " << timer.elapsed() << "ms" << endl;
+        out << "Reads by callsigns / times: " << timer.elapsed() << "ms" << endl;
 
         timer.start();
         for (int t = 0; t < numberOfTimes; t++)
@@ -215,9 +228,23 @@ namespace BlackMiscTest
             {
                 CCallsign callsign("CS" + QString::number(cs));
                 CAircraftSituationList r = situations.findBefore(baseTimeEpoch + 1 + (10 * t)).findByCallsign(callsign);
+                Q_UNUSED(r);
             }
         }
-        out << "Reads by times / callsign: " << timer.elapsed() << "ms" << endl;
+        out << "Reads by times / callsigns: " << timer.elapsed() << "ms" << endl;
+
+        timer.start();
+        for (int t = 0; t < numberOfTimes; t++)
+        {
+            QMap<CCallsign, CAircraftSituationList> splitList = situations.splitPerCallsign();
+            Q_ASSERT(splitList.size() == numberOfCallsigns);
+            for (const CAircraftSituationList &slcs : splitList.values())
+            {
+                CAircraftSituationList r = slcs.findBefore(baseTimeEpoch + 1 + (10 * t));
+                Q_UNUSED(r);
+            }
+        }
+        out << "Split reads by callsigns / times: " << timer.elapsed() << "ms" << endl;
 
         situations.changeImpl<QVector<CAircraftSituation> >();
         out << "Changed to QVector" << endl;
diff --git a/src/blackmisc/avcallsignobjectlist.cpp b/src/blackmisc/avcallsignobjectlist.cpp
index b5f27d1cd..169e1477d 100644
--- a/src/blackmisc/avcallsignobjectlist.cpp
+++ b/src/blackmisc/avcallsignobjectlist.cpp
@@ -99,6 +99,40 @@ namespace BlackMisc
             return r;
         }
 
+        template <class OBJ, class CONTAINER>
+        QMap<CCallsign, CONTAINER> ICallsignObjectList<OBJ, CONTAINER>::splitPerCallsign() const
+        {
+            CONTAINER copyContainer(getContainer());
+            copyContainer.sortByCallsign();
+            QMap<CCallsign, CONTAINER> result;
+            CCallsign cs;
+            for (const OBJ &csObj : copyContainer)
+            {
+                if (csObj.getCallsign().isEmpty())
+                {
+                    Q_ASSERT(false); // there should be no empty callsigns
+                    continue;
+                }
+                if (cs != csObj.getCallsign())
+                {
+                    cs = csObj.getCallsign();
+                    CONTAINER perCallsign({ csObj });
+                    result.insert(cs, perCallsign);
+                }
+                else
+                {
+                    result[cs].push_back(csObj);
+                }
+            }
+            return result;
+        }
+
+        template <class OBJ, class CONTAINER>
+        void ICallsignObjectList<OBJ, CONTAINER>::sortByCallsign()
+        {
+            getContainer().sortBy(&OBJ::getCallsign);
+        }
+
         template <class OBJ, class CONTAINER>
         int ICallsignObjectList<OBJ, CONTAINER>::incrementalUpdateOrAdd(const OBJ &objectBeforeChanges, const CPropertyIndexVariantMap &changedValues)
         {
diff --git a/src/blackmisc/avcallsignobjectlist.h b/src/blackmisc/avcallsignobjectlist.h
index ba68fdefa..92af08291 100644
--- a/src/blackmisc/avcallsignobjectlist.h
+++ b/src/blackmisc/avcallsignobjectlist.h
@@ -57,6 +57,12 @@ namespace BlackMisc
             //! All suffixes with their respective count
             QMap<QString, int> getSuffixes() const;
 
+            //! Split into 0..n containers as per callsign
+            QMap<BlackMisc::Aviation::CCallsign, CONTAINER> splitPerCallsign() const;
+
+            //! Sort by callsign
+            void sortByCallsign();
+
             //! Incremental update or add object
             int incrementalUpdateOrAdd(const OBJ &objectBeforeChanged, const BlackMisc::CPropertyIndexVariantMap &changedValues);