I learned this the hard way as a lead-safe in Kingsville. I had been overhead most of the afternoon, had already trapped aboard twice to hot refuel, and was now overhead watching the cones below getting their traps and watching the sun sinking slowly in the west. As it slipped below the horizon, expecting a steer for home plate, I was dumb-founded when the Boss gave me a "Signal Charlie". I was like, "Wait. You don't understand. I'm a lead-safe, not a stud." It was pretty dark when I trapped, and after getting tied down and climbing out, my good friend, the wing LSO, was waiting next to the jet with a big grin on his face. "We got ya!" he said. He explained that they wanted to get an early start the next day, before the shore based outfits would be ready to launch, so they kept a couple of incomplete studs and a lead-safe overnight to facilitate that. So I got to spend a night on the Lady Lex, eating popcorn, watching the evening movie, and retiring to the LSO bunk space for a nite cap.