diff --git a/megamek/src/megamek/common/Compute.java b/megamek/src/megamek/common/Compute.java
index 9a4781fd69c..cf6aa33ebfe 100644
--- a/megamek/src/megamek/common/Compute.java
+++ b/megamek/src/megamek/common/Compute.java
@@ -2835,10 +2835,10 @@ public static ToHitData getTargetTerrainModifier(Game game, Targetable t,
         boolean isUnderwater = (entityTarget != null)
                                && hex.containsTerrain(Terrains.WATER) && (hex.depth() > 0)
                                && (entityTarget.getElevation() < hex.getLevel());
-        boolean isAboveStructures = (entityTarget != null) && 
-                ((entityTarget.relHeight() > hex.ceiling()) || 
+        boolean isAboveStructures = (entityTarget != null) &&
+                ((entityTarget.relHeight() > hex.ceiling()) ||
                         entityTarget.isAirborne());
-                
+
 
         // if we have in-building combat, it's a +1
         if (attackerInSameBuilding) {
@@ -7538,9 +7538,9 @@ public static Coords calculateArtilleryLead(Game game, Entity ae, Targetable tar
 
             // Try to keep the current position within the homing radius, unless they're real fast...
             if (homing) {
-                leadAmount = (mp * (turnsTilHit)) + HOMING_RADIUS;
+                leadAmount = (mp * (turnsTilHit + 1)) + HOMING_RADIUS;
             } else {
-                leadAmount = mp * (turnsTilHit + 1);
+                leadAmount = mp * (turnsTilHit + 2);
             }
 
             // Guess at the target's movement direction
diff --git a/megamek/unittests/megamek/common/ComputeArtilleryTest.java b/megamek/unittests/megamek/common/ComputeArtilleryTest.java
index 062e6b3be60..d93a1de5df1 100644
--- a/megamek/unittests/megamek/common/ComputeArtilleryTest.java
+++ b/megamek/unittests/megamek/common/ComputeArtilleryTest.java
@@ -107,27 +107,27 @@ public void testComplexCalculateLead() {
         setupTarget(target, new Coords(15, 17), new Coords(15, 21));
         leadPos = Compute.calculateArtilleryLead(mockGame, shooter, target, false);
         assertEquals(15, leadPos.getX());
-        assertEquals(13, leadPos.getY());
+        assertEquals(9, leadPos.getY());
 
         // Mobile target 1 map sheet away to the S (3) direction, speed 4, non-homing
         setupTarget(target, new Coords(15, 25), new Coords(15, 29));
         leadPos = Compute.calculateArtilleryLead(mockGame, shooter, target, false);
         assertEquals(15, leadPos.getX());
-        assertEquals(17, leadPos.getY());
+        assertEquals(13, leadPos.getY());
 
         // Mobile target 1 map sheet away to the S (3) direction, speed 4, homing, should be closer to shooter
         // for better chance to catch mobile unit in TAG-able area
         setupTarget(target, new Coords(15, 25), new Coords(15, 29));
         leadPos = Compute.calculateArtilleryLead(mockGame, shooter, target, true);
         assertEquals(15, leadPos.getX());
-        assertEquals(13, leadPos.getY());
+        assertEquals(9, leadPos.getY());
 
         // Mobile target 1 map sheet away to the NE (1) direction, speed 4, non-homing
         shooterPos = new Coords(0, 35);
         when(shooter.getPosition()).thenReturn(shooterPos);
         setupTarget(target, new Coords(32, 1), new Coords(36, 0));
         leadPos = Compute.calculateArtilleryLead(mockGame, shooter, target, false);
-        assertEquals(24, leadPos.getX());
-        assertEquals(5, leadPos.getY());
+        assertEquals(20, leadPos.getX());
+        assertEquals(7, leadPos.getY());
     }
 }