diff --git a/simgear/scene/tgdb/BucketBox.hxx b/simgear/scene/tgdb/BucketBox.hxx
index 1d43c3df..2e259f89 100644
--- a/simgear/scene/tgdb/BucketBox.hxx
+++ b/simgear/scene/tgdb/BucketBox.hxx
@@ -138,7 +138,7 @@ public:
     {
         // left align longitude offsets
         unsigned offset = _offset[0] - _offset[0] % _bucketSpanAtOffset(_offset[1]);
-        return SGBucket(_offsetToLongitudeDeg(offset), _offsetToLatitudeDeg(_offset[1]));
+        return SGBucket( SGGeod::fromDeg(_offsetToLongitudeDeg(offset), _offsetToLatitudeDeg(_offset[1])) );
     }
 
     BucketBox getParentBox(unsigned level) const