diff --git a/core/src/net/sf/openrocket/masscalc/MassCalculator.java b/core/src/net/sf/openrocket/masscalc/MassCalculator.java
index 411d37b1e..040861910 100644
--- a/core/src/net/sf/openrocket/masscalc/MassCalculator.java
+++ b/core/src/net/sf/openrocket/masscalc/MassCalculator.java
@@ -373,19 +373,27 @@ public class MassCalculator implements Monitorable {
 	
 	private MassData calculateAssemblyMassData(RocketComponent component, String indent) {
 		
-		Coordinate parentCM = component.getComponentCG();
-		double parentIx = component.getRotationalUnitInertia() * parentCM.weight;
-		double parentIt = component.getLongitudinalUnitInertia() * parentCM.weight;
-		MassData parentData = new MassData( parentCM, parentIx, parentIt);
+		Coordinate compCM = component.getComponentCG();
+		double compIx = component.getRotationalUnitInertia() * compCM.weight;
+		double compIt = component.getLongitudinalUnitInertia() * compCM.weight;
 		
 		if (!component.getOverrideSubcomponents()) {
 			if (component.isMassOverridden())
-				parentCM = parentCM.setWeight(MathUtil.max(component.getOverrideMass(), MIN_MASS));
+				compCM = compCM.setWeight(MathUtil.max(component.getOverrideMass(), MIN_MASS));
 			if (component.isCGOverridden())
-				parentCM = parentCM.setXYZ(component.getOverrideCG());
+				compCM = compCM.setXYZ(component.getOverrideCG());
 		}
-		if(( debug) &&( 0 < component.getChildCount()) && (MIN_MASS < parentCM.weight)){
-			System.err.println(String.format("%-32s: %s ",indent+">>["+ component.getName()+"]", parentData.toDebug() ));
+
+		// default if not instanced (instance count == 1)
+		MassData resultantData = new MassData( compCM, compIx, compIt);
+
+		if( debug && (MIN_MASS < compCM.weight)){
+			System.err.println(String.format("%-32s: %s ",indent+"ea["+ component.getName()+"]", compCM ));
+			if( component.isMassOverridden() && component.isMassOverridden() && component.getOverrideSubcomponents()){
+				System.err.println(indent+"   ?["+ component.isMassOverridden()+"]["+ 
+						component.isMassOverridden()+"]["+
+						component.getOverrideSubcomponents()+"]");
+			}
 		}
 		
 		MassData childrenData = MassData.ZERO_DATA;
@@ -401,50 +409,40 @@ public class MassCalculator implements Monitorable {
 
 			childrenData  = childrenData.add( childData );
 		}
-
+		resultantData = resultantData.add( childrenData);
 		
-		MassData resultantData = parentData; // default if not instanced
-		// compensate for component-instancing propogating to children's data 
-		int instanceCount = component.getInstanceCount();
-		boolean hasChildren = ( 0 < component.getChildCount());
-		if (( 1 < instanceCount )&&( hasChildren )){
-//			if(( debug )){
-//				System.err.println(String.format("%s  Found instanceable with %d children: %s (t= %s)", 
-//						indent, component.getInstanceCount(), component.getName(), component.getClass().getSimpleName() ));
-//			}
+		// if instanced, adjust children's data too. 
+		if ( 1 < component.getInstanceCount() ){
+			if( debug ){
+				System.err.println(String.format("%s  Found instanceable with %d children: %s (t= %s)", 
+						indent, component.getInstanceCount(), component.getName(), component.getClass().getSimpleName() ));
+			}
 			
 			final double curIxx = childrenData.getIxx(); // MOI about x-axis
 			final double curIyy = childrenData.getIyy(); // MOI about y axis
 			final double curIzz = childrenData.getIzz(); // MOI about z axis
 			
-			Coordinate eachCM = childrenData.cm;
+			Coordinate templateCM = resultantData.cm;
 			MassData instAccumData = new MassData();  // accumulator for instance MassData
 			Coordinate[] instanceLocations = ((Instanceable) component).getInstanceOffsets();
          	for( Coordinate curOffset : instanceLocations ){
-//         		if( debug){
-//         			//System.err.println(String.format("%-32s: %s", indent+"  inst Accum", instAccumData.toCMDebug() ));
-//         			System.err.println(String.format("%-32s: %s", indent+"  inst Accum", instAccumData.toDebug() ));
-//				}
-         		
-				Coordinate instanceCM = curOffset.add(eachCM);
-				
+         		Coordinate instanceCM = curOffset.add(templateCM);
 				MassData instanceData = new MassData( instanceCM, curIxx, curIyy, curIzz);
 				
 				// 3) Project the template data to the new CM 
 				//    and add to the total
 				instAccumData = instAccumData.add( instanceData);
 			}
-			
-         	childrenData = instAccumData;
+
+         	resultantData = instAccumData;
+         	
+         	if( debug && (MIN_MASS < compCM.weight)){
+    			System.err.println(String.format("%-32s: %s ", indent+"x"+component.getInstanceCount()+"["+component.getName()+"][asbly]", resultantData.toDebug()));
+    		}
+    		
 		}
 
-		// combine the parent's and children's data
-		resultantData = parentData.add( childrenData);
 		
-		if( debug){
-			System.err.println(String.format("%-32s: %s ", indent+"<==>["+component.getName()+"][asbly]", resultantData.toDebug()));
-		}
-
 		// move to parent's reference point
 		resultantData = resultantData.move( component.getOffset() );
 		if( component instanceof ParallelStage ){
diff --git a/core/src/net/sf/openrocket/rocketcomponent/FlightConfiguration.java b/core/src/net/sf/openrocket/rocketcomponent/FlightConfiguration.java
index 9c2bf85ea..00ca73533 100644
--- a/core/src/net/sf/openrocket/rocketcomponent/FlightConfiguration.java
+++ b/core/src/net/sf/openrocket/rocketcomponent/FlightConfiguration.java
@@ -100,20 +100,19 @@ public class FlightConfiguration implements FlightConfigurableParameter<FlightCo
 	
 	
 	public void clearAllStages() {
-		this.setAllStages(false, true);
+		this._setAllStages(false);
+		this.updateMotors();
 	}
 	
 	public void setAllStages() {
-		this.setAllStages(true, true);
+		this._setAllStages(true);
+		this.updateMotors();
 	}
 		
-	private void setAllStages(final boolean _active, final boolean updateRequired ) {
+	private void _setAllStages(final boolean _active) {
 		for (StageFlags cur : stages.values()) {
 			cur.active = _active;
 		}
-		if( updateRequired ){
-			update();
-		}
 	}
 	
 	/** 
@@ -122,7 +121,7 @@ public class FlightConfiguration implements FlightConfigurableParameter<FlightCo
 	 * @param stageNumber  stage number to inactivate
 	 */
 	public void clearStage(final int stageNumber) {
-		setStageActive( stageNumber, false );
+		_setStageActive( stageNumber, false );
 	}
 	
 	/** 
@@ -131,8 +130,9 @@ public class FlightConfiguration implements FlightConfigurableParameter<FlightCo
 	 * @param stageNumber  stage number to activate
 	 */
 	public void setOnlyStage(final int stageNumber) {
-		setAllStages(false, false);
-		setStageActive(stageNumber, true);
+		_setAllStages(false);
+		_setStageActive(stageNumber, true);
+		updateMotors();
 	}
 	
 	/** 
@@ -141,7 +141,7 @@ public class FlightConfiguration implements FlightConfigurableParameter<FlightCo
 	 * @param stageNumber   stage number to flag
 	 * @param _active       inactive (<code>false</code>) or active (<code>true</code>)
 	 */
-	private void setStageActive(final int stageNumber, final boolean _active ) {
+	private void _setStageActive(final int stageNumber, final boolean _active ) {
 		if ((0 <= stageNumber) && (stages.containsKey(stageNumber))) {
 			stages.get(stageNumber).active = _active;
 			return;
@@ -156,6 +156,7 @@ public class FlightConfiguration implements FlightConfigurableParameter<FlightCo
 			flags.active = !flags.active;
 			return;
 		}
+		this.updateMotors();
 		log.error("error: attempt to retrieve via a bad stage number: " + stageNumber);
 	}
 
diff --git a/core/src/net/sf/openrocket/util/TestRockets.java b/core/src/net/sf/openrocket/util/TestRockets.java
index bcb6475d1..8eade7b02 100644
--- a/core/src/net/sf/openrocket/util/TestRockets.java
+++ b/core/src/net/sf/openrocket/util/TestRockets.java
@@ -517,6 +517,7 @@ public class TestRockets {
 		bodytube.setMaterial(material);
 		finset.setMaterial(material);
 		
+		rocket.setSelectedConfiguration( rocket.getFlightConfiguration( fcid[0]));
 		rocket.getSelectedConfiguration().setAllStages();
 		rocket.enableEvents();
 		return rocket;
@@ -1162,6 +1163,7 @@ public class TestRockets {
 		}
 		
 		rocket.enableEvents();
+		rocket.setSelectedConfiguration(config);
 		config.setAllStages();
 		
 		return rocket;
diff --git a/core/test/net/sf/openrocket/masscalc/MassCalculatorTest.java b/core/test/net/sf/openrocket/masscalc/MassCalculatorTest.java
index 1c7c34326..3b05b5fac 100644
--- a/core/test/net/sf/openrocket/masscalc/MassCalculatorTest.java
+++ b/core/test/net/sf/openrocket/masscalc/MassCalculatorTest.java
@@ -7,21 +7,30 @@ import org.junit.Test;
 
 import net.sf.openrocket.masscalc.MassCalculator.MassCalcType;
 import net.sf.openrocket.motor.Motor;
+import net.sf.openrocket.rocketcomponent.BodyTube;
 import net.sf.openrocket.rocketcomponent.FlightConfiguration;
 import net.sf.openrocket.rocketcomponent.InnerTube;
+import net.sf.openrocket.rocketcomponent.NoseCone;
 import net.sf.openrocket.rocketcomponent.ParallelStage;
 import net.sf.openrocket.rocketcomponent.Rocket;
 import net.sf.openrocket.rocketcomponent.RocketComponent;
 import net.sf.openrocket.util.Coordinate;
-import net.sf.openrocket.util.MathUtil;
 import net.sf.openrocket.util.TestRockets;
 import net.sf.openrocket.util.BaseTestCase.BaseTestCase;
 
 public class MassCalculatorTest extends BaseTestCase {
 	
 	// tolerance for compared double test results
-	protected final double EPSILON = MathUtil.EPSILON;
+	protected final double EPSILON = 0.000001;
 	
+	private final double BOOSTER_NOSE_MASS_EA = 0.0222459863653;
+	private final double BOOSTER_BODY_MASS_EA = 0.129886006;
+	private final double BOOSTER_MMT_MASS_EA = 0.01890610458;
+	private final double BOOSTER_TOTAL_DRY_MASS_EACH = 0.4555128227852;
+	private final double BOOSTER_TOTAL_DRY_CMX = 1.246297525;
+	
+	private final double G77_MASS_LAUNCH = 0.123;	
+
 	@Test
 	public void testRocketNoMotors() {
 		Rocket rkt = TestRockets.makeNoMotorRocket();
@@ -52,7 +61,7 @@ public class MassCalculatorTest extends BaseTestCase {
 	}
 	
 	@Test
-	public void testTestComponentMasses() {
+	public void testComponentMasses() {
 		Rocket rkt = TestRockets.makeFalcon9Heavy();
 		rkt.setName("TestRocket."+Thread.currentThread().getStackTrace()[1].getMethodName());
 		
@@ -119,25 +128,26 @@ public class MassCalculatorTest extends BaseTestCase {
 		// ====== ====== ======
 		ParallelStage boosters = (ParallelStage) rkt.getChild(1).getChild(1);
 		{
-			expMass = 0.01530561538;
-			cc= boosters.getChild(0);
-			compMass = cc.getComponentMass();
-			assertEquals(cc.getName()+" mass calculated incorrectly: ", expMass, compMass, EPSILON);
-			
-			expMass = 0.08374229377;
-			cc= boosters.getChild(1);
-			compMass = cc.getComponentMass();
-			assertEquals(cc.getName()+" mass calculated incorrectly: ", expMass, compMass, EPSILON);
-			
-			expMass = 0.018906104589303415;
-			cc= boosters.getChild(1).getChild(0);
-			compMass = cc.getComponentMass();
-			assertEquals(cc.getName()+" mass calculated incorrectly: ", expMass, compMass, EPSILON);
+			expMass = BOOSTER_NOSE_MASS_EA;
+			// think of the casts as an assert that ( child instanceof NoseCone) == true  
+			NoseCone nose = (NoseCone) boosters.getChild(0);
+			compMass = nose.getComponentMass();
+			assertEquals( nose.getName()+" mass calculated incorrectly: ", expMass, compMass, EPSILON);
+
+			expMass = BOOSTER_BODY_MASS_EA;
+			BodyTube body = (BodyTube) boosters.getChild(1);
+			compMass = body.getComponentMass();
+			assertEquals( body.getName()+" mass calculated incorrectly: ", expMass, compMass, EPSILON);
+
+			expMass = BOOSTER_MMT_MASS_EA;
+			InnerTube mmt = (InnerTube)boosters.getChild(1).getChild(0);
+			compMass = mmt.getComponentMass();
+			assertEquals( mmt.getName()+" mass calculated incorrectly: ", expMass, compMass, EPSILON);
 		}
 	}
 	
 	@Test
-	public void testTestComponentMOIs() {
+	public void testComponentMOIs() {
 		Rocket rkt = TestRockets.makeFalcon9Heavy();
 		rkt.setName("TestRocket."+Thread.currentThread().getStackTrace()[1].getMethodName());
 		
@@ -233,18 +243,18 @@ public class MassCalculatorTest extends BaseTestCase {
 		ParallelStage boosters = (ParallelStage) rkt.getChild(1).getChild(1);
 		{
 			cc= boosters.getChild(0);
-			expInertia = 5.20107e-6;
+			expInertia = 1.82665797857e-5;
 			compInertia = cc.getRotationalInertia();
 			assertEquals(cc.getName()+" Rotational MOI calculated incorrectly: ", expInertia, compInertia, EPSILON);
-			expInertia = 0;
+			expInertia = 1.96501191666e-7;
 			compInertia = cc.getLongitudinalInertia();
 			assertEquals(cc.getName()+" Longitudinal MOI calculated incorrectly: ", expInertia, compInertia, EPSILON);
 			
 			cc= boosters.getChild(1);
-			expInertia = 5.02872e-5;
+			expInertia = 1.875878651e-4;
 			compInertia = cc.getRotationalInertia();
 			assertEquals(cc.getName()+" Rotational MOI calculated incorrectly: ", expInertia, compInertia, EPSILON);
-			expInertia = 0.00449140;
+			expInertia = 0.00702104762;
 			compInertia = cc.getLongitudinalInertia();
 			assertEquals(cc.getName()+" Longitudinal MOI calculated incorrectly: ", expInertia, compInertia, EPSILON);
 			
@@ -258,24 +268,21 @@ public class MassCalculatorTest extends BaseTestCase {
 		}
 	}
 	@Test
-	public void testTestBoosterStructureCM() {
+	public void testBoosterStructureCM() {
 		Rocket rocket = TestRockets.makeFalcon9Heavy();
 		rocket.setName("TestRocket."+Thread.currentThread().getStackTrace()[1].getMethodName());
 
 		ParallelStage boosters = (ParallelStage) rocket.getChild(1).getChild(1);
 		int boostNum = boosters.getStageNumber();
 		
-		rocket.getSelectedConfiguration().clearAllStages();
 		rocket.getSelectedConfiguration().setOnlyStage( boostNum);
-//		String treeDump = rocket.toDebugTree();
-//		System.err.println( treeDump);
 		
 		// Validate Boosters
 		MassCalculator mc = new MassCalculator();
 		Coordinate boosterSetCM = mc.getCM( rocket.getSelectedConfiguration(), MassCalcType.NO_MOTORS);
 				
-		double expMass = 0.23590802751203407;
-		double expCMx = 0.9615865040919498;
+		double expMass = BOOSTER_TOTAL_DRY_MASS_EACH;
+		double expCMx = BOOSTER_TOTAL_DRY_CMX;
 		double calcMass = boosterSetCM.weight;
 		assertEquals(" Delta Heavy Booster Mass is incorrect: ", expMass, calcMass, EPSILON);
 		
@@ -295,8 +302,8 @@ public class MassCalculatorTest extends BaseTestCase {
 		Motor activeMotor = mmt.getMotorInstance( rocket.getSelectedConfiguration().getId()).getMotor();
 		String desig = activeMotor.getDesignation();
 		
-		double expLaunchMass = 0.0227; // kg
-		double expSpentMass = 0.0102; // kg
+		double expLaunchMass = 0.0164; // kg
+		double expSpentMass = 0.0131; // kg
 		assertEquals(" Motor Mass "+desig+" is incorrect: ", expLaunchMass, activeMotor.getLaunchCG().weight, EPSILON);
 		assertEquals(" Motor Mass "+desig+" is incorrect: ", expSpentMass, activeMotor.getEmptyCG().weight, EPSILON);
 		
@@ -314,7 +321,8 @@ public class MassCalculatorTest extends BaseTestCase {
 		Rocket rocket = TestRockets.makeFalcon9Heavy();
 		ParallelStage boosters = (ParallelStage) rocket.getChild(1).getChild(1);
 		int boostNum = boosters.getStageNumber();
-		rocket.getSelectedConfiguration().setOnlyStage( boostNum);
+		FlightConfiguration currentConfig = rocket.getSelectedConfiguration();
+		currentConfig.setOnlyStage( boostNum);
 		
 //		String treeDump = rocket.toDebugTree();
 //		System.err.println( treeDump);
@@ -359,22 +367,19 @@ public class MassCalculatorTest extends BaseTestCase {
 
 		ParallelStage boosters = (ParallelStage) rocket.getChild(1).getChild(1);
 		int boostNum = boosters.getStageNumber();
-		//rocket.getDefaultConfiguration().setAllStages(false);
 		rocket.getSelectedConfiguration().setOnlyStage( boostNum);
 		
-//		String treeDump = rocket.toDebugTree();
-//		System.err.println( treeDump);
 		{
 			// Validate Booster Launch Mass
 			MassCalculator mc = new MassCalculator();
-			//mc.debug = true;
 			Coordinate boosterSetCM = mc.getCM( rocket.getSelectedConfiguration(), MassCalcType.LAUNCH_MASS);
 			double calcTotalMass = boosterSetCM.weight;
 			
-			double expTotalMass = 1.219908027512034;
-			double expX = 1.2461238889997992;
-			Coordinate expCM = new Coordinate(expX,0,0, expTotalMass);
+			double expTotalMass = BOOSTER_TOTAL_DRY_MASS_EACH + 8*G77_MASS_LAUNCH;
 			assertEquals(" Booster Launch Mass is incorrect: ", expTotalMass, calcTotalMass, EPSILON);
+			
+			double expX = 1.292808951;
+			Coordinate expCM = new Coordinate(expX,0,0, expTotalMass);
 			assertEquals(" Booster Launch CM.x is incorrect: ", expCM.x, boosterSetCM.x, EPSILON);
 			assertEquals(" Booster Launch CM.y is incorrect: ", expCM.y, boosterSetCM.y, EPSILON);
 			assertEquals(" Booster Launch CM.z is incorrect: ", expCM.z, boosterSetCM.z, EPSILON);
@@ -387,20 +392,20 @@ public class MassCalculatorTest extends BaseTestCase {
 			Coordinate boosterSetCM = mc.getCM( rocket.getSelectedConfiguration(), MassCalcType.BURNOUT_MASS);
 			double calcTotalMass = boosterSetCM.weight;
 			
-			double expTotalMass = 0.7479080275020341;
-			assertEquals(" Booster Launch Mass is incorrect: ", expTotalMass, calcTotalMass, EPSILON);
+			double expTotalMass = BOOSTER_TOTAL_DRY_MASS_EACH + 8*0.064;
+			assertEquals(" Booster Burnout Mass is incorrect: ", expTotalMass, calcTotalMass, EPSILON);
 			
-			double expX =  1.2030731351529202;
+			double expX =  1.282305055;
 			Coordinate expCM = new Coordinate(expX,0,0, expTotalMass);
-			assertEquals(" Booster Launch CM.x is incorrect: ", expCM.x, boosterSetCM.x, EPSILON);
-			assertEquals(" Booster Launch CM.y is incorrect: ", expCM.y, boosterSetCM.y, EPSILON);
-			assertEquals(" Booster Launch CM.z is incorrect: ", expCM.z, boosterSetCM.z, EPSILON);
-			assertEquals(" Booster Launch CM is incorrect: ", expCM, boosterSetCM);
+			assertEquals(" Booster Burnout CM.x is incorrect: ", expCM.x, boosterSetCM.x, EPSILON);
+			assertEquals(" Booster Burnout CM.y is incorrect: ", expCM.y, boosterSetCM.y, EPSILON);
+			assertEquals(" Booster Burnout CM.z is incorrect: ", expCM.z, boosterSetCM.z, EPSILON);
+			assertEquals(" Booster Burnout CM is incorrect: ", expCM, boosterSetCM);
 		}
 	}
 	
 	@Test
-	public void testTestBoosterStructureMOI() {
+	public void testBoosterStructureMOI() {
 		Rocket rocket = TestRockets.makeFalcon9Heavy();
 		rocket.setName("TestRocket."+Thread.currentThread().getStackTrace()[1].getMethodName());
 		FlightConfiguration defaultConfig = rocket.getSelectedConfiguration();
@@ -409,17 +414,14 @@ public class MassCalculatorTest extends BaseTestCase {
 		int boostNum = boosters.getStageNumber();
 		
 		rocket.getSelectedConfiguration().setOnlyStage( boostNum);
-//		String treeDump = rocket.toDebugTree();
-//		System.err.println( treeDump);
 		
 		// Validate Boosters
 		MassCalculator mc = new MassCalculator();
-		//mc.debug = true;
-		double expMOI_axial = .00144619;
+		double expMOI_axial = .00304203;
 		double boosterMOI_xx= mc.getRotationalInertia( defaultConfig, MassCalcType.NO_MOTORS);
 		assertEquals(" Booster x-axis MOI is incorrect: ", expMOI_axial, boosterMOI_xx, EPSILON);
 		
-		double expMOI_tr = 0.01845152840733412;
+		double expMOI_tr = 0.129566277;
 		double boosterMOI_tr= mc.getLongitudinalInertia( defaultConfig, MassCalcType.NO_MOTORS);
 		assertEquals(" Booster transverse MOI is incorrect: ", expMOI_tr, boosterMOI_tr, EPSILON);	
 	}
@@ -428,22 +430,19 @@ public class MassCalculatorTest extends BaseTestCase {
 	public void testBoosterTotalMOI() {
 		Rocket rocket = TestRockets.makeFalcon9Heavy();
 		FlightConfiguration defaultConfig = rocket.getSelectedConfiguration();
-		rocket.setName("TestRocket."+Thread.currentThread().getStackTrace()[1].getMethodName());
+		rocket.setName("TestRocket:F9H:Total_MOI");
 
 		ParallelStage boosters = (ParallelStage) rocket.getChild(1).getChild(1);
 		int boostNum = boosters.getStageNumber();
 		
-		//rocket.getDefaultConfiguration().setAllStages(false);
 		rocket.getSelectedConfiguration().setOnlyStage( boostNum);
-		//String treeDump = rocket.toDebugTree();
-		//System.err.println( treeDump);
 		
 		// Validate Boosters
 		MassCalculator mc = new MassCalculator();
-		final double expMOI_axial = 0.05009613217;//0.00752743;
+		final double expMOI_axial = 0.0516919744;
 		final double boosterMOI_xx= mc.getRotationalInertia( defaultConfig, MassCalcType.LAUNCH_MASS);
 		
-		final double expMOI_tr = 0.05263041249; // 0.0436639379937;
+		final double expMOI_tr = 0.141508294;
 		final double boosterMOI_tr= mc.getLongitudinalInertia( defaultConfig, MassCalcType.LAUNCH_MASS);
 				
 		assertEquals(" Booster x-axis MOI is incorrect: ", expMOI_axial, boosterMOI_xx, EPSILON);
@@ -452,7 +451,7 @@ public class MassCalculatorTest extends BaseTestCase {
 	
 
 	@Test
-	public void testMassOverride() {
+	public void testStageMassOverride() {
 		Rocket rocket = TestRockets.makeFalcon9Heavy();
 		FlightConfiguration config = rocket.getSelectedConfiguration();
 		rocket.setName("TestRocket."+Thread.currentThread().getStackTrace()[1].getMethodName());
@@ -461,24 +460,22 @@ public class MassCalculatorTest extends BaseTestCase {
 		int boostNum = boosters.getStageNumber();
 		config.setOnlyStage( boostNum);
 		
-//		String treeDump = rocket.toDebugTree();
-//		System.err.println( treeDump);
-		
 		double overrideMass = 0.5;
 		boosters.setMassOverridden(true);
 		boosters.setOverrideMass(overrideMass);
 		
+		boosters.setCGOverridden(true);
+		boosters.setOverrideCGX(6.0);
 		{
 			// Validate Mass
 			MassCalculator mc = new MassCalculator();
-			//mc.debug = true;
 			Coordinate boosterSetCM = mc.getCM( rocket.getSelectedConfiguration(), MassCalcType.NO_MOTORS);
 			double calcTotalMass = boosterSetCM.weight;
 			
 			double expTotalMass = overrideMass;
 			assertEquals(" Booster Launch Mass is incorrect: ", expTotalMass, calcTotalMass, EPSILON);
 			
-			double expCMx = 0.9615865040919498;
+			double expCMx = 6.0;
 			Coordinate expCM = new Coordinate( expCMx, 0, 0, expTotalMass);
 			assertEquals(" Booster Launch CM.x is incorrect: ", expCM.x, boosterSetCM.x, EPSILON);
 			assertEquals(" Booster Launch CM.y is incorrect: ", expCM.y, boosterSetCM.y, EPSILON);
@@ -486,20 +483,66 @@ public class MassCalculatorTest extends BaseTestCase {
 			assertEquals(" Booster Launch CM is incorrect: ", expCM, boosterSetCM);
 		
 			// Validate MOI
-			double oldMass = 0.23590802751203407;
-			double scaleMass = overrideMass / oldMass;
-			//mc.debug = true;
-			double expMOI_axial = .00144619 * scaleMass;
+			double expMOI_axial = .00333912717;
 			double boosterMOI_xx= mc.getRotationalInertia( config, MassCalcType.NO_MOTORS);
 			assertEquals(" Booster x-axis MOI is incorrect: ", expMOI_axial, boosterMOI_xx, EPSILON);
 			
-			double expMOI_tr = 0.01845152840733412 * scaleMass;
+			double expMOI_tr = 0.142220231;
 			double boosterMOI_tr= mc.getLongitudinalInertia( config, MassCalcType.NO_MOTORS);
 			assertEquals(" Booster transverse MOI is incorrect: ", expMOI_tr, boosterMOI_tr, EPSILON);	
 		}
 		
 	}
 	
+	@Test
+	public void testComponentMassOverride() {
+		Rocket rocket = TestRockets.makeFalcon9Heavy();
+		FlightConfiguration config = rocket.getSelectedConfiguration();
+		rocket.setName("TestRocket."+Thread.currentThread().getStackTrace()[1].getMethodName());
+
+		ParallelStage boosters = (ParallelStage) rocket.getChild(1).getChild(1);
+		int boostNum = boosters.getStageNumber();
+		config.setOnlyStage( boostNum);
+		
+		NoseCone nose = (NoseCone)boosters.getChild(0);
+		nose.setMassOverridden(true);
+		nose.setOverrideMass( 0.71 );
+
+		BodyTube body = (BodyTube)boosters.getChild(1);
+		body.setMassOverridden(true);
+		body.setOverrideMass( 0.622 );
+
+		InnerTube mmt = (InnerTube)boosters.getChild(1).getChild(0);
+		mmt.setMassOverridden(true);
+		mmt.setOverrideMass( 0.213 );
+		
+		{
+			// Validate Mass
+			MassCalculator mc = new MassCalculator();
+			Coordinate boosterSetCM = mc.getCM( rocket.getSelectedConfiguration(), MassCalcType.NO_MOTORS);
+			double calcTotalMass = boosterSetCM.weight;
+			
+			double expTotalMass = 4.368;
+			assertEquals(" Booster Launch Mass is incorrect: ", expTotalMass, calcTotalMass, EPSILON);
+			
+			double expCMx = 1.20642422735;
+			Coordinate expCM = new Coordinate( expCMx, 0, 0, expTotalMass);
+			assertEquals(" Booster Launch CM.x is incorrect: ", expCM.x, boosterSetCM.x, EPSILON);
+			assertEquals(" Booster Launch CM.y is incorrect: ", expCM.y, boosterSetCM.y, EPSILON);
+			assertEquals(" Booster Launch CM.z is incorrect: ", expCM.z, boosterSetCM.z, EPSILON);
+			assertEquals(" Booster Launch CM is incorrect: ", expCM, boosterSetCM);
+		
+			// Validate MOI
+			double expMOI_axial = 0.0257485;
+			double boosterMOI_xx= mc.getRotationalInertia( config, MassCalcType.NO_MOTORS);
+			assertEquals(" Booster x-axis MOI is incorrect: ", expMOI_axial, boosterMOI_xx, EPSILON);
+			
+			double expMOI_tr = 1.633216231;
+			double boosterMOI_tr= mc.getLongitudinalInertia( config, MassCalcType.NO_MOTORS);
+			assertEquals(" Booster transverse MOI is incorrect: ", expMOI_tr, boosterMOI_tr, EPSILON);	
+		}
+		
+	}
 
 	@Test
 	public void testCMOverride() {
@@ -511,23 +554,29 @@ public class MassCalculatorTest extends BaseTestCase {
 		int boostNum = boosters.getStageNumber();
 		config.setOnlyStage( boostNum);
 		
-		//String treeDump = rocket.toDebugTree();
-		//System.err.println( treeDump);
-		
-		double overrideCMx = 0.5;
-		boosters.setCGOverridden(true);
-		boosters.setOverrideCGX(overrideCMx); // only allows x-axis corrections
+		NoseCone nose = (NoseCone)boosters.getChild(0);
+		nose.setCGOverridden(true);
+		nose.setOverrideCGX(0.22);
+
+		BodyTube body = (BodyTube)boosters.getChild(1);
+		body.setCGOverridden(true);
+		body.setOverrideCGX( 0.433);
+
+		InnerTube mmt = (InnerTube)boosters.getChild(1).getChild(0);
+		mmt.setCGOverridden(true);
+		mmt.setOverrideCGX( 0.395 );
+
 		{
 			// Validate Mass
 			MassCalculator mc = new MassCalculator();
 			//mc.debug = true;
 			Coordinate boosterSetCM = mc.getCM( rocket.getSelectedConfiguration(), MassCalcType.NO_MOTORS);
 			
-			double expMass = 0.23590802751203407;
+			double expMass = BOOSTER_TOTAL_DRY_MASS_EACH;
 			double calcTotalMass = boosterSetCM.weight;
 			assertEquals(" Booster Launch Mass is incorrect: ", expMass, calcTotalMass, EPSILON);
 			
-			double expCMx = overrideCMx; //0.9615865040919498;
+			double expCMx = 1.38741685552577;
 			Coordinate expCM = new Coordinate( expCMx, 0, 0, expMass);
 			assertEquals(" Booster Launch CM.x is incorrect: ", expCM.x, boosterSetCM.x, EPSILON);
 			assertEquals(" Booster Launch CM.y is incorrect: ", expCM.y, boosterSetCM.y, EPSILON);
@@ -535,11 +584,11 @@ public class MassCalculatorTest extends BaseTestCase {
 			assertEquals(" Booster Launch CM is incorrect: ", expCM, boosterSetCM);
 		
 			// Validate MOI
-			double expMOI_axial = .00144619 ;
+			double expMOI_axial = 0.00304203;
 			double boosterMOI_xx= mc.getRotationalInertia( config, MassCalcType.NO_MOTORS);
 			assertEquals(" Booster x-axis MOI is incorrect: ", expMOI_axial, boosterMOI_xx, EPSILON);
 			
-			double expMOI_tr = 0.01845152840733412 ;
+			double expMOI_tr = 0.1893499746;
 			double boosterMOI_tr= mc.getLongitudinalInertia( config, MassCalcType.NO_MOTORS);
 			assertEquals(" Booster transverse MOI is incorrect: ", expMOI_tr, boosterMOI_tr, EPSILON);	
 		}
diff --git a/core/test/net/sf/openrocket/rocketcomponent/FlightConfigurationTest.java b/core/test/net/sf/openrocket/rocketcomponent/FlightConfigurationTest.java
index 6caeb0d97..c8beaa563 100644
--- a/core/test/net/sf/openrocket/rocketcomponent/FlightConfigurationTest.java
+++ b/core/test/net/sf/openrocket/rocketcomponent/FlightConfigurationTest.java
@@ -7,13 +7,6 @@ import static org.junit.Assert.assertTrue;
 
 import org.junit.Test;
 
-import net.sf.openrocket.motor.Manufacturer;
-import net.sf.openrocket.motor.Motor;
-import net.sf.openrocket.motor.MotorConfiguration;
-import net.sf.openrocket.motor.ThrustCurveMotor;
-import net.sf.openrocket.optimization.rocketoptimization.TestRocketOptimizationFunction;
-import net.sf.openrocket.rocketcomponent.RocketComponent.Position;
-import net.sf.openrocket.util.Coordinate;
 import net.sf.openrocket.util.MathUtil;
 import net.sf.openrocket.util.TestRockets;
 import net.sf.openrocket.util.BaseTestCase.BaseTestCase;
@@ -157,19 +150,12 @@ public class FlightConfigurationTest extends BaseTestCase {
 	public void testConfigurationSwitching() {
 		/* Setup */
 		Rocket rkt = TestRockets.makeEstesAlphaIII();
-		//FlightConfiguration config = rkt.getSelectedConfiguration();
 		
 		InnerTube smmt = (InnerTube)rkt.getChild(0).getChild(1).getChild(2);
-		System.err.println( smmt.toMotorDebug());
 		
-		final String configDump= rkt.toDebugConfigs();
-		System.err.println("configs:\n" +configDump);
-//		final String treedump = rkt.toDebugTree();
-//		System.err.println("treedump: \n" + treedump);
-		
-		
-		//int actualMotorCount = smmt.getM
-		//assertThat("number of motor configurations doesn't actually match.", actualMotorCount, equalTo(expectedMotorCount));
+		int expectedMotorCount = 5;
+		int actualMotorCount = smmt.getMotorCount();
+		assertThat("number of motor configurations doesn't match.", actualMotorCount, equalTo(expectedMotorCount));
 		
 		// test that all configurations correctly loaded:
 		int expectedConfigCount = 5;
diff --git a/core/test/net/sf/openrocket/rocketcomponent/TransitionTest.java b/core/test/net/sf/openrocket/rocketcomponent/TransitionTest.java
new file mode 100644
index 000000000..5e709f077
--- /dev/null
+++ b/core/test/net/sf/openrocket/rocketcomponent/TransitionTest.java
@@ -0,0 +1,173 @@
+package net.sf.openrocket.rocketcomponent;
+
+import static org.hamcrest.CoreMatchers.equalTo;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertThat;
+
+import org.junit.Test;
+
+import net.sf.openrocket.util.MathUtil;
+import net.sf.openrocket.util.TestRockets;
+import net.sf.openrocket.util.BaseTestCase.BaseTestCase;
+
+public class TransitionTest extends BaseTestCase {
+	protected final double EPSILON = MathUtil.EPSILON*1000;
+	
+	@Test
+	public void testVerifyConicNose(){
+		NoseCone nose = new NoseCone(Transition.Shape.CONICAL, 0.06, 0.01);
+		assertEquals("nose cone length is wrong ", 0.06, nose.getLength(), EPSILON );
+		assertEquals("nose cone fore radius is wrong ", 0.00, nose.getForeRadius(), EPSILON );
+		assertEquals("nose cone aft radius is wrong ", 0.01, nose.getAftRadius(), EPSILON );
+		assertThat("nose cone shape type is wrong ", Transition.Shape.CONICAL, equalTo(nose.getType()));
+		assertEquals("nose cone shape parameter is wrong ", 0.0, nose.getShapeParameter(), EPSILON );
+		
+		assertEquals("bad shape - conical forward ", 0.0, nose.getRadius(0.00), EPSILON );
+		assertEquals("bad shape - conical forward ", 0.0025, nose.getRadius(0.015), EPSILON );
+		assertEquals("bad shape - conical forward ", 0.005, nose.getRadius(0.03), EPSILON );
+		assertEquals("bad shape - conical forward ", 0.0075, nose.getRadius(0.045), EPSILON );
+		assertEquals("bad shape - conical forward ", 0.01, nose.getRadius(0.06), EPSILON );
+		
+	}
+
+	@Test
+	public void testVerifyForwardConicTransition(){
+		Transition nose = new Transition();
+		nose.setType( Transition.Shape.CONICAL);
+		nose.setForeRadius( 0.5);
+		nose.setAftRadius( 1.0);
+		nose.setLength( 5.0);
+		
+		assertEquals("nose cone length is wrong ", 5.0, nose.getLength(), EPSILON );
+		assertEquals("nose cone fore radius is wrong ", 0.5, nose.getForeRadius(), EPSILON );
+		assertEquals("nose cone aft radius is wrong ", 1.0, nose.getAftRadius(), EPSILON );
+		assertThat("nose cone shape type is wrong ", Transition.Shape.CONICAL, equalTo(nose.getType()));
+		assertEquals("nose cone shape parameter is wrong ", 0.0, nose.getShapeParameter(), EPSILON );
+		
+		assertEquals("bad shape - conical forward transition", 0.5, nose.getRadius(0.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.6, nose.getRadius(1.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.7, nose.getRadius(2.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.8, nose.getRadius(3.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.9, nose.getRadius(4.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 1.0, nose.getRadius(5.0), EPSILON );
+		
+	}
+
+
+	@Test
+	public void testVerifyBackwardConicTransition(){
+		Transition nose = new Transition();
+		nose.setType( Transition.Shape.CONICAL);
+		nose.setForeRadius( 1.0);
+		nose.setAftRadius( 0.5);
+		nose.setLength( 5.0);
+		
+		assertEquals("nose cone length is wrong ", 5.0, nose.getLength(), EPSILON );
+		assertEquals("nose cone fore radius is wrong ", 1.0, nose.getForeRadius(), EPSILON );
+		assertEquals("nose cone aft radius is wrong ", 0.5, nose.getAftRadius(), EPSILON );
+		assertThat("nose cone shape type is wrong ", Transition.Shape.CONICAL, equalTo(nose.getType()));
+		assertEquals("nose cone shape parameter is wrong ", 0.0, nose.getShapeParameter(), EPSILON );
+		
+		assertEquals("bad shape - conical forward transition", 1.0, nose.getRadius(0.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.9, nose.getRadius(1.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.8, nose.getRadius(2.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.7, nose.getRadius(3.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.6, nose.getRadius(4.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.5, nose.getRadius(5.0), EPSILON );
+		
+	}
+
+
+	@Test
+	public void testVerifyOgiveNoseCone(){
+		Transition nose = new Transition();
+		nose.setType( Transition.Shape.OGIVE);
+		nose.setForeRadius( 0.0);
+		nose.setAftRadius( 1.0);
+		nose.setLength( 8.0);
+		
+		assertEquals("nose cone length is wrong ", 8.0, nose.getLength(), EPSILON );
+		assertEquals("nose cone fore radius is wrong ", 0.0, nose.getForeRadius(), EPSILON );
+		assertEquals("nose cone aft radius is wrong ", 1.0, nose.getAftRadius(), EPSILON );
+		assertThat("nose cone shape type is wrong ", Transition.Shape.OGIVE, equalTo(nose.getType()));
+		assertEquals("nose cone shape parameter is wrong ", 1.0, nose.getShapeParameter(), EPSILON );
+
+		assertEquals("bad shape - conical forward transition", 0.0, nose.getRadius(0.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.23720214511, nose.getRadius(1.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.44135250736, nose.getRadius(2.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.61308144666, nose.getRadius(3.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.75290684574, nose.getRadius(4.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.86124225056, nose.getRadius(5.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.93840316661, nose.getRadius(6.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.98461174156, nose.getRadius(7.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 1.0, nose.getRadius(8.0), EPSILON );
+		
+	}
+
+	@Test
+	public void testVerifyForwardOgiveTransition(){
+		Transition nose = new Transition();
+		nose.setType( Transition.Shape.OGIVE);
+		nose.setForeRadius( 0.44135);
+		nose.setAftRadius( 1.0);
+		nose.setLength( 6.0);
+		
+		assertEquals("nose cone length is wrong ", 6.0, nose.getLength(), EPSILON );
+		assertEquals("nose cone fore radius is wrong ", 0.44135, nose.getForeRadius(), EPSILON );
+		assertEquals("nose cone aft radius is wrong ", 1.0, nose.getAftRadius(), EPSILON );
+		assertThat("nose cone shape type is wrong ", Transition.Shape.OGIVE, equalTo(nose.getType()));
+		assertEquals("nose cone shape parameter is wrong ", 1.0, nose.getShapeParameter(), EPSILON );
+		
+		assertEquals("bad shape - conical forward transition", 0.44135250736, nose.getRadius(0.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.61308144666, nose.getRadius(1.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.75290684574, nose.getRadius(2.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.86124225056, nose.getRadius(3.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.93840316661, nose.getRadius(4.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.98461174156, nose.getRadius(5.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 1.0, nose.getRadius(6.0), EPSILON );
+		
+	}
+	
+	@Test
+	public void testVerifyBackwardOgiveTransition(){
+		Transition nose = new Transition();
+		nose.setType( Transition.Shape.OGIVE);
+		nose.setForeRadius( 1.0);
+		nose.setAftRadius( 0.44135);
+		nose.setLength( 6.0);
+		
+		assertEquals("nose cone length is wrong ", 6.0, nose.getLength(), EPSILON );
+		assertEquals("nose cone fore radius is wrong ", 1.0, nose.getForeRadius(), EPSILON );
+		assertEquals("nose cone aft radius is wrong ", 0.44135, nose.getAftRadius(), EPSILON );
+		assertThat("nose cone shape type is wrong ", Transition.Shape.OGIVE, equalTo(nose.getType()));
+		assertEquals("nose cone shape parameter is wrong ",1.0, nose.getShapeParameter(), EPSILON );
+		
+		assertEquals("bad shape - conical forward transition", 1.0, nose.getRadius(0.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.98461174156, nose.getRadius(1.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.93840316661, nose.getRadius(2.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.86124225056, nose.getRadius(3.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.75290684574, nose.getRadius(4.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.61308144666, nose.getRadius(5.0), EPSILON );
+		assertEquals("bad shape - conical forward transition", 0.44135250736, nose.getRadius(6.0), EPSILON );
+		
+	
+	
+	}
+	
+	@Test
+	public void testStockIntegration(){
+		Rocket rocket = TestRockets.makeEstesAlphaIII();
+		NoseCone nose = (NoseCone)rocket.getChild(0).getChild(0);
+		
+		assertEquals("Alpha3 nose cone length is wrong ", 0.07, nose.getLength(), EPSILON );
+		assertEquals("Alpha3 nose cone fore radius is wrong ", 0.00, nose.getForeRadius(), EPSILON );
+		assertEquals("Alpha3 nose cone aft radius is wrong ", 0.012, nose.getAftRadius(), EPSILON );
+		assertThat("Alpha3 nose cone shape type is wrong ", Transition.Shape.OGIVE, equalTo(nose.getType()));
+		assertEquals("Alpha3 nose cone shape parameter is wrong ", 1.0, nose.getShapeParameter(), EPSILON );
+	
+		assertEquals("Alpha3 nose cone aft shoulder length is wrong ", 0.02, nose.getAftShoulderLength(), EPSILON );
+		assertEquals("Alpha3 nose cone aft shoulder radius is wrong ", 0.011, nose.getAftShoulderRadius(), EPSILON );
+		
+	}
+	
+}