diff --git a/components/nif/controlled.cpp b/components/nif/controlled.cpp
index 9db0c4a6f..bf391d388 100644
--- a/components/nif/controlled.cpp
+++ b/components/nif/controlled.cpp
@@ -54,7 +54,10 @@ namespace Nif
     {
         Controlled::read(nif);
 
-        /*unknown*/nif->getFloat();
+        float decay = nif->getFloat();
+        if (decay != 0.f)
+            nif->file->warn("Unhandled gravity decay factor");
+
         mForce = nif->getFloat();
         mType = nif->getUInt();
         mPosition = nif->getVector3();