The way we do it, yes, we've issued multiple recommendations over the years relating to certification issues on a variety of aircraft. We were talking about the Sikorsky S-92, and just to clarify, they are making improvements to that aircraft to allow it to fly 30 minutes without oil. They have responded to us.
We annually reassess the responses. When we find responses fully satisfactory, we say so. When there's more that needs to be done, we can rate it as satisfactory in part, or even unsatisfactory. Our ultimate tool is our recommendations, or even our watch list, if we find that there's a specific safety issue that isn't being addressed.