diff --git a/core/src/main/java/info/openrocket/core/simulation/DataBranch.java b/core/src/main/java/info/openrocket/core/simulation/DataBranch.java
new file mode 100644
index 000000000..8f1e6cae8
--- /dev/null
+++ b/core/src/main/java/info/openrocket/core/simulation/DataBranch.java
@@ -0,0 +1,71 @@
+package info.openrocket.core.simulation;
+
+import info.openrocket.core.util.Monitorable;
+
+import java.util.List;
+
+/**
+ * A branch of data / collection of data points for a specific type of data.
+ * @param <T> the type of data in this branch
+ */
+public interface DataBranch<T extends DataType> extends Monitorable {
+	/**
+	 * Return an array of values for the specified variable type.
+	 *
+	 * @param type	the variable type.
+	 * @return		a list of the variable values, or <code>null</code> if
+	 * 				the variable type hasn't been added to this branch.
+	 */
+	List<Double> get(T type);
+
+	/**
+	 * Return the value of the specified type at the specified index.
+	 * @param type the variable type
+	 * @param index the data index of the value
+	 * @return the value at the specified index
+	 */
+	Double getByIndex(T type, int index);
+
+	/**
+	 * Return the last value of the specified type in the branch, or NaN if the type is
+	 * unavailable.
+	 *
+	 * @param type	the parameter type.
+	 * @return		the last value in this branch, or NaN.
+	 */
+	double getLast(T type);
+
+	/**
+	 * Return the minimum value of the specified type in the branch, or NaN if the type
+	 * is unavailable.
+	 *
+	 * @param type	the parameter type.
+	 * @return		the minimum value in this branch, or NaN.
+	 */
+	double getMinimum(T type);
+
+	/**
+	 * Return the maximum value of the specified type in the branch, or NaN if the type
+	 * is unavailable.
+	 *
+	 * @param type	the parameter type.
+	 * @return		the maximum value in this branch, or NaN.
+	 */
+	double getMaximum(T type);
+
+	/**
+	 * Return the number of data points in this branch.
+	 */
+	int getLength();
+
+	/**
+	 * Return the variable types included in this branch.  The types are sorted in their
+	 * natural order.
+	 */
+	T[] getTypes();
+
+	/**
+	 * Return the branch name.
+	 */
+	String getName();
+}
diff --git a/core/src/main/java/info/openrocket/core/simulation/DataType.java b/core/src/main/java/info/openrocket/core/simulation/DataType.java
new file mode 100644
index 000000000..99e5b5738
--- /dev/null
+++ b/core/src/main/java/info/openrocket/core/simulation/DataType.java
@@ -0,0 +1,9 @@
+package info.openrocket.core.simulation;
+
+import info.openrocket.core.util.UnitValue;
+
+/**
+ * A type of data that can be stored in a {@link DataBranch}.
+ */
+public interface DataType extends UnitValue {
+}
diff --git a/core/src/main/java/info/openrocket/core/simulation/FlightDataBranch.java b/core/src/main/java/info/openrocket/core/simulation/FlightDataBranch.java
index 10fdd1147..e866abc9e 100644
--- a/core/src/main/java/info/openrocket/core/simulation/FlightDataBranch.java
+++ b/core/src/main/java/info/openrocket/core/simulation/FlightDataBranch.java
@@ -29,7 +29,7 @@ import info.openrocket.core.util.Mutable;
  * 
  * @author Sampo Niskanen <sampo.niskanen@iki.fi>
  */
-public class FlightDataBranch implements Monitorable {
+public class FlightDataBranch implements DataBranch<FlightDataType> {
 	
 	/** The name of this flight data branch. */
 	private final String name;
@@ -228,26 +228,19 @@ public class FlightDataBranch implements Monitorable {
 		}
 	}
 	
-	/**
-	 * Return the branch name.
-	 */
+	@Override
 	public String getName() {
 		return name;
 	}
 	
-	/**
-	 * Return the variable types included in this branch.  The types are sorted in their
-	 * natural order.
-	 */
+	@Override
 	public FlightDataType[] getTypes() {
 		FlightDataType[] array = values.keySet().toArray(new FlightDataType[0]);
 		Arrays.sort(array);
 		return array;
 	}
 	
-	/**
-	 * Return the number of data points in this branch.
-	 */
+	@Override
 	public int getLength() {
 		for (ArrayList<Double> doubles : values.values()) {
 			return doubles.size();
@@ -255,13 +248,7 @@ public class FlightDataBranch implements Monitorable {
 		return 0;
 	}
 	
-	/**
-	 * Return an array of values for the specified variable type.
-	 * 
-	 * @param type	the variable type.
-	 * @return		a list of the variable values, or <code>null</code> if
-	 * 				the variable type hasn't been added to this branch.
-	 */
+	@Override
 	public List<Double> get(FlightDataType type) {
 		ArrayList<Double> list = values.get(type);
 		if (list == null)
@@ -269,12 +256,7 @@ public class FlightDataBranch implements Monitorable {
 		return list.clone();
 	}
 
-	/**
-	 * Return the value of the specified type at the specified index.
-	 * @param type the variable type
-	 * @param index the data index of the value
-	 * @return the value at the specified index
-	 */
+	@Override
 	public Double getByIndex(FlightDataType type, int index) {
 		if (index < 0 || index >= getLength()) {
 			throw new IllegalArgumentException("Index out of bounds");
@@ -286,13 +268,7 @@ public class FlightDataBranch implements Monitorable {
 		return list.get(index);
 	}
 
-	/**
-	 * Return the last value of the specified type in the branch, or NaN if the type is
-	 * unavailable.
-	 * 
-	 * @param type	the parameter type.
-	 * @return		the last value in this branch, or NaN.
-	 */
+	@Override
 	public double getLast(FlightDataType type) {
 		ArrayList<Double> list = values.get(type);
 		if (list == null || list.isEmpty())
@@ -300,13 +276,7 @@ public class FlightDataBranch implements Monitorable {
 		return list.get(list.size() - 1);
 	}
 	
-	/**
-	 * Return the minimum value of the specified type in the branch, or NaN if the type
-	 * is unavailable.
-	 * 
-	 * @param type	the parameter type.
-	 * @return		the minimum value in this branch, or NaN.
-	 */
+	@Override
 	public double getMinimum(FlightDataType type) {
 		Double v = minValues.get(type);
 		if (v == null)
@@ -314,13 +284,7 @@ public class FlightDataBranch implements Monitorable {
 		return v;
 	}
 	
-	/**
-	 * Return the maximum value of the specified type in the branch, or NaN if the type
-	 * is unavailable.
-	 * 
-	 * @param type	the parameter type.
-	 * @return		the maximum value in this branch, or NaN.
-	 */
+	@Override
 	public double getMaximum(FlightDataType type) {
 		Double v = maxValues.get(type);
 		if (v == null)
diff --git a/core/src/main/java/info/openrocket/core/simulation/FlightDataType.java b/core/src/main/java/info/openrocket/core/simulation/FlightDataType.java
index 91744034e..ad9449236 100644
--- a/core/src/main/java/info/openrocket/core/simulation/FlightDataType.java
+++ b/core/src/main/java/info/openrocket/core/simulation/FlightDataType.java
@@ -34,7 +34,7 @@ import info.openrocket.core.util.StringUtils;
  * 
  * @author Sampo Niskanen <sampo.niskanen@iki.fi>
  */
-public class FlightDataType implements Comparable<FlightDataType>, Groupable<FlightDataTypeGroup>, UnitValue {
+public class FlightDataType implements Comparable<FlightDataType>, Groupable<FlightDataTypeGroup>, DataType {
 	private static final Translator trans = Application.getTranslator();
 	private static final Logger log = LoggerFactory.getLogger(FlightDataType.class);
 
@@ -490,10 +490,12 @@ public class FlightDataType implements Comparable<FlightDataType>, Groupable<Fli
 		return symbol;
 	}
 
+	@Override
 	public UnitGroup getUnitGroup() {
 		return units;
 	}
 
+	@Override
 	public FlightDataTypeGroup getGroup() {
 		return group;
 	}