diff --git a/dumux/freeflow/navierstokes/problem.hh b/dumux/freeflow/navierstokes/problem.hh
index 12073bcb2077dcf5dceb96cb5ab78e8ab10ef7a8..9fb566006d5fb3ceb44fe20c8b50a58dd2d2eded 100644
--- a/dumux/freeflow/navierstokes/problem.hh
+++ b/dumux/freeflow/navierstokes/problem.hh
@@ -479,7 +479,7 @@ public:
         const auto& scv = fvGeometry.scv(scvf.insideScvIdx());
 
         // create a unit normal vector oriented in positive coordinate direction
-        GlobalPosition orientation;
+        GlobalPosition orientation(0.0);
         orientation[scv.dofAxis()] = 1.0;
 
         // du/dy + dv/dx = alpha/sqrt(K) * (u_boundary-uPM)