diff --git a/OpenRA.Game/Map/Map.cs b/OpenRA.Game/Map/Map.cs
index 293ba3cbef..04768aa2ac 100644
--- a/OpenRA.Game/Map/Map.cs
+++ b/OpenRA.Game/Map/Map.cs
@@ -564,5 +564,14 @@ namespace OpenRA
 				r.Next(Bounds.Left, Bounds.Right),
 				r.Next(Bounds.Top, Bounds.Bottom));
 		}
+
+		public WRange DistanceToEdge(WPos pos, WVec dir)
+		{
+			var tl = Bounds.TopLeftAsCPos().TopLeft;
+			var br = Bounds.BottomRightAsCPos().BottomRight;
+			var x = dir.X == 0 ? int.MaxValue : ((dir.X < 0 ? tl.X : br.X) - pos.X) / dir.X;
+			var y = dir.Y == 0 ? int.MaxValue : ((dir.Y < 0 ? tl.Y : br.Y) - pos.Y) / dir.Y;
+			return new WRange(Math.Min(x, y) * dir.Length);
+		}
 	}
 }
diff --git a/OpenRA.Game/WorldUtils.cs b/OpenRA.Game/WorldUtils.cs
index d9e5e4f44c..305087fd12 100644
--- a/OpenRA.Game/WorldUtils.cs
+++ b/OpenRA.Game/WorldUtils.cs
@@ -100,15 +100,6 @@ namespace OpenRA
 					: (edge ? w.Map.Bounds.Top : w.Map.Bounds.Bottom));
 		}
 
-		public static WRange DistanceToMapEdge(this World w, WPos pos, WVec dir)
-		{
-			var tl = w.Map.Bounds.TopLeftAsCPos().TopLeft;
-			var br = w.Map.Bounds.BottomRightAsCPos().BottomRight;
-			var x = dir.X == 0 ? int.MaxValue : ((dir.X < 0 ? tl.X : br.X) - pos.X) / dir.X;
-			var y = dir.Y == 0 ? int.MaxValue : ((dir.Y < 0 ? tl.Y : br.Y) - pos.Y) / dir.Y;
-			return new WRange(Math.Min(x, y) * dir.Length);
-		}
-
 		public static bool HasVoices(this Actor a)
 		{
 			var selectable = a.Info.Traits.GetOrDefault<SelectableInfo>();
diff --git a/OpenRA.Mods.RA/SupportPowers/AirstrikePower.cs b/OpenRA.Mods.RA/SupportPowers/AirstrikePower.cs
index e0eb70c3b5..d6394aa99d 100644
--- a/OpenRA.Mods.RA/SupportPowers/AirstrikePower.cs
+++ b/OpenRA.Mods.RA/SupportPowers/AirstrikePower.cs
@@ -65,8 +65,8 @@ namespace OpenRA.Mods.RA
 
 			var altitude = self.World.Map.Rules.Actors[info.UnitType].Traits.Get<PlaneInfo>().CruiseAltitude.Range;
 			var target = order.TargetLocation.CenterPosition + new WVec(0, 0, altitude);
-			var startEdge = target - (self.World.DistanceToMapEdge(target, -delta) + info.Cordon).Range * delta / 1024;
-			var finishEdge = target + (self.World.DistanceToMapEdge(target, delta) + info.Cordon).Range * delta / 1024;
+			var startEdge = target - (self.World.Map.DistanceToEdge(target, -delta) + info.Cordon).Range * delta / 1024;
+			var finishEdge = target + (self.World.Map.DistanceToEdge(target, delta) + info.Cordon).Range * delta / 1024;
 
 			Actor flare = null;
 			Actor camera = null;