diff --git a/samples/blackmiscquantities/sample_quantities_avionics.pro b/samples/blackmiscquantities/sample_quantities_avionics.pro
index a69afcd41..59cf6ab98 100644
--- a/samples/blackmiscquantities/sample_quantities_avionics.pro
+++ b/samples/blackmiscquantities/sample_quantities_avionics.pro
@@ -10,10 +10,6 @@ CONFIG   -= app_bundle
 DEPENDPATH += . ../../src/blackmisc
 INCLUDEPATH += . ../../src
 
-SOURCES += main.cpp \
-    samplesphysicalquantities.cpp \
-    samplesaviation.cpp
-
 win32-msvc* {
     PRE_TARGETDEPS += ../../lib/blackmisc.lib
     LIBS += ../../lib/blackmisc.lib
@@ -26,6 +22,5 @@ win32-msvc* {
 
 DESTDIR = ../../bin
 
-HEADERS += \
-    samplesphysicalquantities.h \
-    samplesaviation.h
+HEADERS += *.h
+SOURCES += *.cpp
diff --git a/samples/blackmiscquantities/samplesphysicalquantities.cpp b/samples/blackmiscquantities/samplesphysicalquantities.cpp
index 6594cc157..0a88b6be5 100644
--- a/samples/blackmiscquantities/samplesphysicalquantities.cpp
+++ b/samples/blackmiscquantities/samplesphysicalquantities.cpp
@@ -110,6 +110,9 @@ int CSamplesPhysicalQuantities::samples()
     ti2.switchUnit(CTimeUnit::ms());
     qDebug() << ti1 << ti2;
 
+    CAcceleration ac1(10, CAccelerationUnit::m_s2());
+    qDebug() << ac1;
+
     // bye
     qDebug() << "-----------------------------------------------";
     return 0;
diff --git a/samples/blackmiscvectorgeo/samplesvectormatrix.h b/samples/blackmiscvectorgeo/samplesvectormatrix.h
index 5e2495375..2af44df54 100644
--- a/samples/blackmiscvectorgeo/samplesvectormatrix.h
+++ b/samples/blackmiscvectorgeo/samplesvectormatrix.h
@@ -26,4 +26,4 @@ private:
 };
 } // namespace
 
-#endif
+#endif // guard
diff --git a/src/blackmisc/blackmisc.pro b/src/blackmisc/blackmisc.pro
index f2be19eb4..ffa483da8 100644
--- a/src/blackmisc/blackmisc.pro
+++ b/src/blackmisc/blackmisc.pro
@@ -5,19 +5,16 @@ TEMPLATE = lib
 CONFIG += staticlib
 
 INCLUDEPATH += ..
-
 # DEPENDPATH += . .. // BlackMisc should be independent
-# PRECOMPILED_HEADER = stdpch.h
 
+# PRECOMPILED_HEADER = stdpch.h
 precompile_header:!isEmpty(PRECOMPILED_HEADER) {
  DEFINES += USING_PCH
  }
 
 DEFINES += LOG_IN_FILE
 
-HEADERS += *.h \
-    pqacceleration.h
-
+HEADERS += *.h
 SOURCES += *.cpp
 
 DESTDIR = ../../lib
diff --git a/src/blackmisc/mathmatrix3x3.h b/src/blackmisc/mathmatrix3x3.h
index 970c09d8c..4291d5265 100644
--- a/src/blackmisc/mathmatrix3x3.h
+++ b/src/blackmisc/mathmatrix3x3.h
@@ -166,10 +166,10 @@ public:
 
     /*!
      * \brief Get row
-     * \param column
+     * \param row
      * \return
      */
-    CMatrix1x3 getRow(int column) const;
+    CMatrix1x3 getRow(int row) const;
 
 };
 
diff --git a/src/blackmisc/mathvector3dbase.h b/src/blackmisc/mathvector3dbase.h
index b0a421550..1dfd1f6ba 100644
--- a/src/blackmisc/mathvector3dbase.h
+++ b/src/blackmisc/mathvector3dbase.h
@@ -375,7 +375,7 @@ public:
      */
     double length()const
     {
-        return this->m_i * this->m_j + this->m_k;
+        return this->m_i + this->m_j + this->m_k;
     }
 
     /*!
diff --git a/src/blackmisc/pqallquantities.h b/src/blackmisc/pqallquantities.h
index a56d9844d..0381c0b60 100644
--- a/src/blackmisc/pqallquantities.h
+++ b/src/blackmisc/pqallquantities.h
@@ -1,5 +1,10 @@
-#ifndef PQUNITSALL_H
-#define PQUNITSALL_H
+/*  Copyright (C) 2013 VATSIM Community / contributors
+ *  This Source Code Form is subject to the terms of the Mozilla Public
+ *  License, v. 2.0. If a copy of the MPL was not distributed with this
+ *  file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef BLACKMISC_PQUNITSALL_H
+#define BLACKMISC_PQUNITSALL_H
 
 // All units / quantities, required for the instantiations of the template
 // especially as CRTP is used.
@@ -14,5 +19,6 @@
 #include "blackmisc/pqtemperature.h"
 #include "blackmisc/pqangle.h"
 #include "blackmisc/pqtime.h"
+#include "blackmisc/pqacceleration.h"
 
-#endif // PQUNITSALL_H
+#endif // guard
diff --git a/src/blackmisc/pqconstants.h b/src/blackmisc/pqconstants.h
index 035cc8072..4a022ea88 100644
--- a/src/blackmisc/pqconstants.h
+++ b/src/blackmisc/pqconstants.h
@@ -1,4 +1,4 @@
-/*  Copyright (C) 2013 VATSIM Community
+/*  Copyright (C) 2013 VATSIM Community / contributors
  *  This Source Code Form is subject to the terms of the Mozilla Public
  *  License, v. 2.0. If a copy of the MPL was not distributed with this
  *  file, You can obtain one at http://mozilla.org/MPL/2.0/. */
diff --git a/src/blackmisc/pqphysicalquantity.cpp b/src/blackmisc/pqphysicalquantity.cpp
index 1ac0219cf..40aefdd20 100644
--- a/src/blackmisc/pqphysicalquantity.cpp
+++ b/src/blackmisc/pqphysicalquantity.cpp
@@ -276,13 +276,15 @@ template <class MU, class PQ> bool CPhysicalQuantity<MU, PQ>::operator <=(const
 /*
  * Switch to another unit
  */
-template <class MU, class PQ> CPhysicalQuantity<MU, PQ> &CPhysicalQuantity<MU, PQ>::switchUnit(const MU &newUnit)
+template <class MU, class PQ> PQ &CPhysicalQuantity<MU, PQ>::switchUnit(const MU &newUnit)
 {
-    if (this->m_unit == newUnit) return *this;
-    double cf = this->m_unit.conversionToUnit(this->m_unitValueD, newUnit);
-    this->m_unit = newUnit;
-    this->setUnitValue(cf);
-    return *this;
+    if (this->m_unit != newUnit)
+    {
+        double cf = this->m_unit.conversionToUnit(this->m_unitValueD, newUnit);
+        this->m_unit = newUnit;
+        this->setUnitValue(cf);
+    }
+    return static_cast<PQ &>(*this);
 }
 
 /*
@@ -407,6 +409,7 @@ template class CPhysicalQuantity<CTemperatureUnit, CTemperature>;
 template class CPhysicalQuantity<CSpeedUnit, CSpeed>;
 template class CPhysicalQuantity<CAngleUnit, CAngle>;
 template class CPhysicalQuantity<CTimeUnit, CTime>;
+template class CPhysicalQuantity<CAccelerationUnit, CAcceleration>;
 
 } // namespace
 } // namespace
diff --git a/src/blackmisc/pqphysicalquantity.h b/src/blackmisc/pqphysicalquantity.h
index 5415325ea..6db60b34c 100644
--- a/src/blackmisc/pqphysicalquantity.h
+++ b/src/blackmisc/pqphysicalquantity.h
@@ -1,4 +1,4 @@
-/*  Copyright (C) 2013 VATSIM Community / authors
+/*  Copyright (C) 2013 VATSIM Community / contributors
  *  This Source Code Form is subject to the terms of the Mozilla Public
  *  License, v. 2.0. If a copy of the MPL was not distributed with this
  *  file, You can obtain one at http://mozilla.org/MPL/2.0/. */
@@ -108,11 +108,11 @@ public:
     }
 
     /*!
-     * \brief Switch unit, e.g. feet meter
+     * \brief Switch unit, e.g. feet to meter
      * \param newUnit
      * \return
      */
-    CPhysicalQuantity &switchUnit(const MU &newUnit);
+    PQ &switchUnit(const MU &newUnit);
 
     /*!
      * \brief Value in SI base unit? Meter is an SI base unit, hertz not!
diff --git a/src/blackmisc/pqunits.cpp b/src/blackmisc/pqunits.cpp
index 3676f36ec..396f05332 100644
--- a/src/blackmisc/pqunits.cpp
+++ b/src/blackmisc/pqunits.cpp
@@ -1,4 +1,4 @@
-/*  Copyright (C) 2013 VATSIM Community
+/*  Copyright (C) 2013 VATSIM Community / contributors
  *  This Source Code Form is subject to the terms of the Mozilla Public
  *  License, v. 2.0. If a copy of the MPL was not distributed with this
  *  file, You can obtain one at http://mozilla.org/MPL/2.0/. */
@@ -69,7 +69,8 @@ double CAngleUnit::conversionSexagesimalToSi(const CMeasurementUnit &, double va
 QString CAngleUnit::toQStringRounded(double value, int digits) const
 {
     QString s;
-    if ((*this) == CAngleUnit::sexagesimalDeg()) {
+    if ((*this) == CAngleUnit::sexagesimalDeg())
+    {
         // special formatting for sexagesimal degrees
         double de = floor(value);
         double mi = floor((value - de) * 100.0);
@@ -77,7 +78,9 @@ QString CAngleUnit::toQStringRounded(double value, int digits) const
         QString ses = QLocale::system().toString(se, 'f', 2);
         s = QString::number(de).append(this->getUnitName()).append(QString::number(mi))
             .append("'").append(ses).append("\"");
-    } else {
+    }
+    else
+    {
         s = CMeasurementUnit::toQStringRounded(value, digits);
     }
     return s;
diff --git a/src/blackmisc/pqunits.h b/src/blackmisc/pqunits.h
index 5c7529a02..e3c5d6d10 100644
--- a/src/blackmisc/pqunits.h
+++ b/src/blackmisc/pqunits.h
@@ -731,7 +731,7 @@ public:
      */
     static const CAccelerationUnit &m_s2()
     {
-        static CAccelerationUnit ms2("meter/second^2", "m/s^2", true, false, 1, CMeasurementPrefix::None(), 1);
+        static CAccelerationUnit ms2("meter/second²", "m/s²", true, false, 1, CMeasurementPrefix::None(), 1);
         return ms2;
     }
 
@@ -741,13 +741,11 @@ public:
      */
     static const CAccelerationUnit &ft_s2()
     {
-        static CAccelerationUnit fts2("feet/seconds^s", "ft/s^2", true, false, 3.28084, CMeasurementPrefix::m(), 0);
+        static CAccelerationUnit fts2("feet/seconds²", "ft/s²", true, false, 3.28084, CMeasurementPrefix::m(), 0);
         return fts2;
     }
 };
 
-
-
 } // namespace
 } // namespace
 #endif // guard
diff --git a/tests/blackmisc/test_blackmisc.pro b/tests/blackmisc/test_blackmisc.pro
index 8a5299da1..68427a185 100644
--- a/tests/blackmisc/test_blackmisc.pro
+++ b/tests/blackmisc/test_blackmisc.pro
@@ -8,18 +8,9 @@ CONFIG   -= app_bundle
 
 DEPENDPATH += . ../../src/blackmisc
 INCLUDEPATH += . ../../src
-SOURCES += main.cpp testmain.cpp \
-    testphysicalquantities.cpp \
-    testvectormatrix.cpp \
-    testaviation.cpp \
-    testgeo.cpp
 
-HEADERS += testmain.h \
-    blackmisctest.h \
-    testphysicalquantities.h \
-    testvectormatrix.h \
-    testaviation.h \
-    testgeo.h
+HEADERS += *.h
+SOURCES += *.cpp
 
 win32-msvc* {
     PRE_TARGETDEPS +=  ../../lib/blackmisc.lib
diff --git a/tests/blackmisc/testphysicalquantities.cpp b/tests/blackmisc/testphysicalquantities.cpp
index 267de0b65..2fd7b0ba6 100644
--- a/tests/blackmisc/testphysicalquantities.cpp
+++ b/tests/blackmisc/testphysicalquantities.cpp
@@ -10,14 +10,6 @@ using namespace BlackMisc::PhysicalQuantities;
 namespace BlackMiscTest
 {
 
-/*
- * Constructor
- */
-CTestPhysicalQuantities::CTestPhysicalQuantities(QObject *parent) : QObject(parent)
-{
-    // void
-}
-
 /*
  * Basic unit tests for physical units
  */
@@ -163,6 +155,22 @@ void CTestPhysicalQuantities::timeTests()
     QVERIFY2(t1.convertedSiValueToInteger() == 3600, "1hour shall be 3600s");
 }
 
+/*
+ * Test acceleration
+ */
+void CTestPhysicalQuantities::accelerationTests()
+{
+    CLength oneMeter(1, CLengthUnit::m());
+    double ftFactor = oneMeter.switchUnit(CLengthUnit::ft()).unitValueToDouble();
+
+    CAcceleration a1(10.0, CAccelerationUnit::m_s2());
+    CAcceleration a2(a1);
+    a1.switchUnit(CAccelerationUnit::ft_s2());
+    QVERIFY2(a1 == a2, "Accelerations should be similar");
+    QVERIFY2(BlackMisc::Math::CMath::round(a1.unitValueToDouble() * ftFactor, 6) == a2.unitValueToDoubleRounded(6),
+             "Numerical values should be equal");
+}
+
 /*
  * Just testing obvious memory create / destruct flaws
  */
@@ -182,7 +190,7 @@ void CTestPhysicalQuantities::memoryTests()
 }
 
 /*
- * @brief Just testing obvious memory create / destruct flaws
+ * Some very basic arithmetic tests on the PQs
  */
 void CTestPhysicalQuantities::basicArithmetic()
 {
@@ -195,5 +203,7 @@ void CTestPhysicalQuantities::basicArithmetic()
     QVERIFY2(p3 == p1, "Pressure needs to be the same (1time)");
     p3 = p3 - p3;
     QVERIFY2(p3.unitValueToDouble() == 0, "Value needs to be zero");
+    p3 = CPressure(1013, CPressureUnit::hPa());
+    QVERIFY2(p3 * 1.5 == 1.5 * p3, "Basic commutative test on PQ failed");
 }
 } // namespace
diff --git a/tests/blackmisc/testphysicalquantities.h b/tests/blackmisc/testphysicalquantities.h
index 9a8f6c123..8f159b1df 100644
--- a/tests/blackmisc/testphysicalquantities.h
+++ b/tests/blackmisc/testphysicalquantities.h
@@ -24,49 +24,64 @@ public:
      * \brief Standard test case constructor
      * \param parent
      */
-    explicit CTestPhysicalQuantities(QObject *parent = 0);
+    explicit CTestPhysicalQuantities(QObject *parent = 0) : QObject(parent) {}
 
 private slots:
     /*!
      * \brief Basic unit tests for physical units
      */
     void unitsBasics();
+
     /*!
      * \brief Basic tests around length
      */
     void lengthBasics();
+
     /*!
      * \brief Basic tests about speed
      */
     void speedBasics();
+
     /*!
      * \brief Frequency tests
      */
     void frequencyTests();
+
     /*!
      * \brief Testing angles (degrees / radians)
      */
     void angleTests();
+
     /*!
      * \brief Testing angles
      */
     void massTests();
+
     /*!
      * \brief Testing pressure
      */
     void pressureTests();
+
     /*!
      * \brief Testing temperature
      */
     void temperatureTests();
+
     /*!
      * \brief Testing time
      */
     void timeTests();
+
+    /*!
+     * \brief Testing acceleration
+     */
+    void accelerationTests();
+
     /*!
      * \brief Testing construction / destruction in memory
      */
     void memoryTests();
+
     /*!
      * \brief Basic arithmetic such as +/-
      */
diff --git a/tests/blackmisc/testvectormatrix.cpp b/tests/blackmisc/testvectormatrix.cpp
index 9cd78ad88..2a9b5616d 100644
--- a/tests/blackmisc/testvectormatrix.cpp
+++ b/tests/blackmisc/testvectormatrix.cpp
@@ -28,6 +28,9 @@ void CTestVectorMatrix::vectorBasics()
     CVector3D v7(3, 4, 5);
     QVERIFY2(v6.crossProduct(v7) == CVector3D(-2, 4, -2), "Cross product is wrong");
     QVERIFY2(v6.dotProduct(v7) == 26, "Dot product is wrong, 26 expected");
+    QVERIFY2(v6.length() == (1 + 2 + 3), "Wrong vector length");
+    QVERIFY2(v6.lengthSquared() == (1 + 4 + 9), "Wrong squared vector length");
+    QVERIFY2(v6.magnitude() == sqrt(1.0 + 4.0 + 9.0), "Wrong vector magnitude");
 }
 
 /*
@@ -68,8 +71,13 @@ void CTestVectorMatrix::matrixBasics()
     QVERIFY2(m1(0, 0) == 1 && m1(1, 0) == 2 && m1(0, 2) == 3, "Index error");
     CMatrix3x3 mi = m1.inverse(invertible);
     CMatrix3x3 mid = m1 * mi;
-    mid.round();
-    QVERIFY2(mid.isIdentity(), qPrintable(QString("Multiply with inverse should be identity: %1").arg(mid.toQString())));
+    QVERIFY2(mid.isIdentityEpsilon(), qPrintable(QString("Multiply with inverse should be identity: %1").arg(mid.toQString())));
+
+    m1.setToIdentity();
+    CMatrix3x1 mc1 = m1.getColumn(0);
+    CMatrix1x3 mr2 = m1.getRow(1);
+    QVERIFY2(mc1 == CMatrix3x1(1, 0, 0), "Wrong column 0");
+    QVERIFY2(mr2 == CMatrix1x3(0, 1, 0), "Wrong row 1");
 }
 
 } // namespace