The Bullfrog is carrier ready. It has the engine shroud on for slowing down and the arrestor hook. It honestly can probably land on a carrier without either of those as well. As for the Grasshopper, it worked the first time, however I could not control the carrier. I remember reading something about a physics lock in the guide, and I'm going to assume it's an older problem that I could easily fix, but I had enough of KSP that day and shut it down. As for the Narwhal, it still doesn't work. I haven't tried the other two. (By the way, the Grasshopper worked the first time but I wasn't able to replicate that in two more tries. It probably will work if I continue to re-launch it, but like I said, I shut KSP down.)