diff --git a/core/src/net/sf/openrocket/simulation/BasicEventSimulationEngine.java b/core/src/net/sf/openrocket/simulation/BasicEventSimulationEngine.java
index 69fdf3d3d..c17daff2d 100644
--- a/core/src/net/sf/openrocket/simulation/BasicEventSimulationEngine.java
+++ b/core/src/net/sf/openrocket/simulation/BasicEventSimulationEngine.java
@@ -173,7 +173,7 @@ public class BasicEventSimulationEngine implements SimulationEngine {
 				} else {
 					
 					// Check ground hit after liftoff
-					if ((currentStatus.getRocketPosition().z < 0) && !currentStatus.isLanded()) {
+					if ((currentStatus.getRocketPosition().z < MathUtil.EPSILON) && !currentStatus.isLanded()) {
 						addEvent(new FlightEvent(FlightEvent.Type.GROUND_HIT, currentStatus.getSimulationTime()));
 						
 						// addEvent(new FlightEvent(FlightEvent.Type.SIMULATION_END, currentStatus.getSimulationTime()));
diff --git a/core/src/net/sf/openrocket/simulation/BasicLandingStepper.java b/core/src/net/sf/openrocket/simulation/BasicLandingStepper.java
index a111d1227..f6fe081a0 100644
--- a/core/src/net/sf/openrocket/simulation/BasicLandingStepper.java
+++ b/core/src/net/sf/openrocket/simulation/BasicLandingStepper.java
@@ -8,7 +8,11 @@ import net.sf.openrocket.util.GeodeticComputationStrategy;
 import net.sf.openrocket.util.MathUtil;
 import net.sf.openrocket.util.WorldCoordinate;
 
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 public class BasicLandingStepper extends AbstractSimulationStepper {
+	private static final Logger log = LoggerFactory.getLogger(BasicLandingStepper.class);
 	
 	private static final double RECOVERY_TIME_STEP = 0.5;
 	
@@ -65,13 +69,35 @@ public class BasicLandingStepper extends AbstractSimulationStepper {
 		
 
 
-		// Select time step
+		// Select tentative time step
 		double timeStep = MathUtil.min(0.5 / linearAcceleration.length(), RECOVERY_TIME_STEP);
 		
 		// Perform Euler integration
-		status.setRocketPosition(status.getRocketPosition().add(status.getRocketVelocity().multiply(timeStep)).
-				add(linearAcceleration.multiply(MathUtil.pow2(timeStep) / 2)));
+		Coordinate newPosition = status.getRocketPosition().add(status.getRocketVelocity().multiply(timeStep)).
+			add(linearAcceleration.multiply(MathUtil.pow2(timeStep) / 2));
+
+		// If I've hit the ground, recalculate time step and position
+		if (newPosition.z < 0) {
+
+			final double a = linearAcceleration.z;
+			final double v = status.getRocketVelocity().z;
+			final double z0 = status.getRocketPosition().z;
+
+			// The new timestep is the solution of
+			// 1/2 at^2 + vt + z0 = 0
+			timeStep = (-v - Math.sqrt(v*v - 2*a*z0))/a;
+			
+			newPosition = status.getRocketPosition().add(status.getRocketVelocity().multiply(timeStep)).
+				add(linearAcceleration.multiply(MathUtil.pow2(timeStep) / 2));
+
+			// avoid rounding error in new altitude
+			newPosition = newPosition.setZ(0);
+		}
+		
+		status.setRocketPosition(newPosition);
+			
 		status.setRocketVelocity(status.getRocketVelocity().add(linearAcceleration.multiply(timeStep)));
+		airSpeed = status.getRocketVelocity().add(windSpeed);
 		status.setSimulationTime(status.getSimulationTime() + timeStep);
 		
 
@@ -139,6 +165,7 @@ public class BasicLandingStepper extends AbstractSimulationStepper {
 		data.setValue(FlightDataType.TYPE_TIME_STEP, timeStep);
 		data.setValue(FlightDataType.TYPE_COMPUTATION_TIME,
 				(System.nanoTime() - status.getSimulationStartWallTime()) / 1000000000.0);
+		log.debug("time " + data.getLast(FlightDataType.TYPE_TIME) + ", altitude " + data.getLast(FlightDataType.TYPE_ALTITUDE) + ", velocity " + data.getLast(FlightDataType.TYPE_VELOCITY_Z));
 	}
 	
 }
diff --git a/core/src/net/sf/openrocket/simulation/GroundStepper.java b/core/src/net/sf/openrocket/simulation/GroundStepper.java
index db9ea466d..49c8b5b4f 100644
--- a/core/src/net/sf/openrocket/simulation/GroundStepper.java
+++ b/core/src/net/sf/openrocket/simulation/GroundStepper.java
@@ -20,70 +20,5 @@ public class GroundStepper extends AbstractSimulationStepper {
 	@Override
 	public void step(SimulationStatus status, double timeStep) throws SimulationException {
 		log.trace("step:  position=" + status.getRocketPosition() + ", velocity=" + status.getRocketVelocity());
-				
-		status.setRocketVelocity(Coordinate.ZERO);
-		status.setRocketRotationVelocity(Coordinate.ZERO);
-		status.setRocketPosition(status.getRocketPosition().setZ(0));
-		
-		// Store data
-		FlightDataBranch data = status.getFlightData();
-		boolean extra = status.getSimulationConditions().isCalculateExtras();
-		data.addPoint();
-		
-		data.setValue(FlightDataType.TYPE_TIME, status.getSimulationTime());
-		data.setValue(FlightDataType.TYPE_ALTITUDE, status.getRocketPosition().z);
-		data.setValue(FlightDataType.TYPE_POSITION_X, status.getRocketPosition().x);
-		data.setValue(FlightDataType.TYPE_POSITION_Y, status.getRocketPosition().y);
-		if (extra) {
-			data.setValue(FlightDataType.TYPE_POSITION_XY,
-						  MathUtil.hypot(status.getRocketPosition().x, status.getRocketPosition().y));
-			data.setValue(FlightDataType.TYPE_POSITION_DIRECTION,
-						  Math.atan2(status.getRocketPosition().y, status.getRocketPosition().x));
-			
-			data.setValue(FlightDataType.TYPE_VELOCITY_XY,
-						  MathUtil.hypot(status.getRocketVelocity().x, status.getRocketVelocity().y));
-			data.setValue(FlightDataType.TYPE_ACCELERATION_XY, 0.0);
-			
-			data.setValue(FlightDataType.TYPE_ACCELERATION_TOTAL, 0.0);
-			
-			data.setValue(FlightDataType.TYPE_REYNOLDS_NUMBER, Double.POSITIVE_INFINITY);
-		}
-		
-		data.setValue(FlightDataType.TYPE_LATITUDE, status.getRocketWorldPosition().getLatitudeRad());
-		data.setValue(FlightDataType.TYPE_LONGITUDE, status.getRocketWorldPosition().getLongitudeRad());
-		data.setValue(FlightDataType.TYPE_GRAVITY, modelGravity(status));
-		
-		data.setValue(FlightDataType.TYPE_CORIOLIS_ACCELERATION, 0.0);
-		
-		data.setValue(FlightDataType.TYPE_VELOCITY_Z, status.getRocketVelocity().z);
-		data.setValue(FlightDataType.TYPE_ACCELERATION_Z, 0.0);
-		
-		data.setValue(FlightDataType.TYPE_VELOCITY_TOTAL, 0.0);
-		data.setValue(FlightDataType.TYPE_MACH_NUMBER, 0.0);
-
-
-		// Calculate mass data
-		double rocketMass = calculateStructureMass(status).getMass();
-		double motorMass = calculateMotorMass(status).getMass();
-		
-		double mass = rocketMass + motorMass;
-		data.setValue(FlightDataType.TYPE_MASS, mass);
-		data.setValue(FlightDataType.TYPE_MOTOR_MASS, motorMass);
-		
-		data.setValue(FlightDataType.TYPE_THRUST_FORCE, 0.0);
-		data.setValue(FlightDataType.TYPE_DRAG_FORCE, 0.0);
-		
-		data.setValue(FlightDataType.TYPE_WIND_VELOCITY, modelWindVelocity(status).length());
-		
-		AtmosphericConditions atmosphere = modelAtmosphericConditions(status);
-		data.setValue(FlightDataType.TYPE_AIR_TEMPERATURE, atmosphere.getTemperature());
-		data.setValue(FlightDataType.TYPE_AIR_PRESSURE, atmosphere.getPressure());
-		data.setValue(FlightDataType.TYPE_SPEED_OF_SOUND, atmosphere.getMachSpeed());
-		
-		data.setValue(FlightDataType.TYPE_TIME_STEP, timeStep);
-		data.setValue(FlightDataType.TYPE_COMPUTATION_TIME,
-					  (System.nanoTime() - status.getSimulationStartWallTime()) / 1000000000.0);
-
-		status.setSimulationTime(status.getSimulationTime() + timeStep);		
 	}
 }
diff --git a/core/src/net/sf/openrocket/util/MathUtil.java b/core/src/net/sf/openrocket/util/MathUtil.java
index e1ae86c12..e948ee8d5 100644
--- a/core/src/net/sf/openrocket/util/MathUtil.java
+++ b/core/src/net/sf/openrocket/util/MathUtil.java
@@ -331,13 +331,13 @@ public class MathUtil {
 		}
 		
 		int length = domain.size();
-		if (length <= 1 || t < domain.get(0) || t > domain.get(length - 1)) {
+		if (length <= 1 || t < domain.get(0) || t > domain.get(length - 1) + EPSILON) {
 			return Double.NaN;
 		}
 		
 		// Look for the index of the right end point.
 		int right = 1;
-		while (t > domain.get(right)) {
+		while (t > domain.get(right) + EPSILON) {
 			right++;
 		}
 		int left = right - 1;
diff --git a/swing/resources-src/datafiles/components b/swing/resources-src/datafiles/components
index c9bd1a6f5..8304c0fd3 160000
--- a/swing/resources-src/datafiles/components
+++ b/swing/resources-src/datafiles/components
@@ -1 +1 @@
-Subproject commit c9bd1a6f539aab4bb724ecbdb54e65100a33e701
+Subproject commit 8304c0fd3dc80d65c40af4da83268ec1b32931d6