diff --git a/src/Airspace/airspace.cxx b/src/Airspace/airspace.cxx
index 075a1568..05063d69 100644
--- a/src/Airspace/airspace.cxx
+++ b/src/Airspace/airspace.cxx
@@ -123,36 +123,32 @@ const string airspace_texture_path = "/usr/local/share/FlightGear/data/Textures/
 
 // return the horizontal tile span factor based on latitude
 double sg_bucket_span( double l ) {
-    if ( l >= 89.0 ) {
-	return 360.0;
-    } else if ( l >= 88.0 ) {
-	return 8.0;
-    } else if ( l >= 86.0 ) {
-	return 4.0;
-    } else if ( l >= 83.0 ) {
-	return 2.0;
-    } else if ( l >= 76.0 ) {
-	return 1.0;
-    } else if ( l >= 62.0 ) {
-	return 0.5;
-    } else if ( l >= 22.0 ) {
-	return 0.25;
-    } else if ( l >= -22.0 ) {
-	return 0.125;
-    } else if ( l >= -62.0 ) {
-	return 0.25;
-    } else if ( l >= -76.0 ) {
-	return 0.5;
-    } else if ( l >= -83.0 ) {
-	return 1.0;
-    } else if ( l >= -86.0 ) {
-	return 2.0;
-    } else if ( l >= -88.0 ) {
-	return 4.0;
-    } else if ( l >= -89.0 ) {
-	return 8.0;
+    if (l >= 89.0) {
+        return 12.0;
+    } else if (l >= 86.0) {
+        return 4.0;
+    } else if (l >= 83.0) {
+        return 2.0;
+    } else if (l >= 76.0) {
+        return 1.0;
+    } else if (l >= 62.0) {
+        return 0.5;
+    } else if (l >= 22.0) {
+        return 0.25;
+    } else if (l >= -22.0) {
+        return 0.125;
+    } else if (l >= -62.0) {
+        return 0.25;
+    } else if (l >= -76.0) {
+        return 0.5;
+    } else if (l >= -83.0) {
+        return 1.0;
+    } else if (l >= -86.0) {
+        return 2.0;
+    } else if (l >= -89.0) {
+        return 4.0;
     } else {
-	return 360.0;
+        return 12.0;
     }
 }
 
diff --git a/src/Prep/Tower/calc-tile.pl b/src/Prep/Tower/calc-tile.pl
index 44dc1a40..81472d4c 100644
--- a/src/Prep/Tower/calc-tile.pl
+++ b/src/Prep/Tower/calc-tile.pl
@@ -30,9 +30,7 @@ my $DIRSEP = '/';
 sub bucket_span {
   my ($lat) = (@_);
   if ($lat>= 89.0 ) {
-    return 360.0;
-  } elsif ($lat>= 88.0 ) {
-    return 8.0;
+    return 12.0;
   } elsif ($lat>= 86.0 ) {
     return 4.0;
   } elsif ($lat>= 83.0 ) {
@@ -53,12 +51,10 @@ sub bucket_span {
     return 1.0;
   } elsif ($lat>= -86.0 ) {
     return 2.0;
-  } elsif ($lat>= -88.0 ) {
-    return 4.0;
   } elsif ($lat>= -89.0 ) {
-    return 8.0;
+    return 4.0;
   } else {
-    return 360.0;
+    return 12.0;
   }
 }