diff --git a/core/src/net/sf/openrocket/aerodynamics/barrowman/TubeCalc.java b/core/src/net/sf/openrocket/aerodynamics/barrowman/TubeCalc.java
index 8595e1efb..08f391c6d 100644
--- a/core/src/net/sf/openrocket/aerodynamics/barrowman/TubeCalc.java
+++ b/core/src/net/sf/openrocket/aerodynamics/barrowman/TubeCalc.java
@@ -3,8 +3,8 @@ package net.sf.openrocket.aerodynamics.barrowman;
 import net.sf.openrocket.aerodynamics.AerodynamicForces;
 import net.sf.openrocket.aerodynamics.FlightConditions;
 import net.sf.openrocket.aerodynamics.WarningSet;
-import net.sf.openrocket.rocketcomponent.LaunchLug;
 import net.sf.openrocket.rocketcomponent.RocketComponent;
+import net.sf.openrocket.rocketcomponent.Tube;
 import net.sf.openrocket.util.MathUtil;
 import net.sf.openrocket.util.Transformation;
 
@@ -15,13 +15,14 @@ public abstract class TubeCalc extends RocketComponentCalc {
 	
 	public TubeCalc(RocketComponent component) {
 		super(component);
-		
-		LaunchLug lug = (LaunchLug)component;
-		double ld = lug.getLength() / (2*lug.getOuterRadius());
+
+		Tube tube = (Tube)component;
+
+		double ld = tube.getLength() / (2*tube.getOuterRadius());
 		
 		CDmul = Math.max(1.3 - ld, 1);
-		refArea = Math.PI * MathUtil.pow2(lug.getOuterRadius()) - 
-				  Math.PI * MathUtil.pow2(lug.getInnerRadius()) * Math.max(1 - ld, 0);
+		refArea = Math.PI * MathUtil.pow2(tube.getOuterRadius()) - 
+				  Math.PI * MathUtil.pow2(tube.getInnerRadius()) * Math.max(1 - ld, 0);
 	}
 
 }
diff --git a/core/src/net/sf/openrocket/rocketcomponent/LaunchLug.java b/core/src/net/sf/openrocket/rocketcomponent/LaunchLug.java
index 9541bb0cd..f6fa6f65b 100644
--- a/core/src/net/sf/openrocket/rocketcomponent/LaunchLug.java
+++ b/core/src/net/sf/openrocket/rocketcomponent/LaunchLug.java
@@ -17,7 +17,7 @@ import net.sf.openrocket.util.MathUtil;
 import net.sf.openrocket.util.StateChangeListener;
 
 
-public class LaunchLug extends ExternalComponent implements AnglePositionable, BoxBounded, Coaxial, LineInstanceable, InsideColorComponent {
+public class LaunchLug extends Tube implements AnglePositionable, BoxBounded, LineInstanceable, InsideColorComponent {
 	
 	private static final Translator trans = Application.getTranslator();
 	
diff --git a/core/src/net/sf/openrocket/rocketcomponent/TubeFinSet.java b/core/src/net/sf/openrocket/rocketcomponent/TubeFinSet.java
index 685198726..0cba415ce 100644
--- a/core/src/net/sf/openrocket/rocketcomponent/TubeFinSet.java
+++ b/core/src/net/sf/openrocket/rocketcomponent/TubeFinSet.java
@@ -17,7 +17,7 @@ import net.sf.openrocket.rocketcomponent.position.RadiusMethod;
 import net.sf.openrocket.startup.Application;
 import net.sf.openrocket.util.*;
 
-public class TubeFinSet extends ExternalComponent implements AxialPositionable, BoxBounded, RingInstanceable, InsideColorComponent {
+public class TubeFinSet extends Tube implements AxialPositionable, BoxBounded, RingInstanceable, InsideColorComponent {
 	private static final Translator trans = Application.getTranslator();
 	
 	private final static double DEFAULT_RADIUS = 0.025;