Schirra--he's the one who does the cold-capsule commercials--delivers the second Apollo astronaut autobiography of the season, a jolly, cranky, adolescent self-portrait that shares neither the intensity nor the arrogance of Frank Borman's Countdown (p. 1203). ""I've really had one hell of a good time,"" chortles Schirra, who devotes a huge amount of space to recounting astronautical practical jokes. There's the time the guys blew up a Life photographer's jeep, the time the guys smuggled a boa constrictor into the office, the time. . . But it wasn't all a party, as Schirra recalls his long, hard climb through Annapolis, Korea (where he flew 90 combat missions), and test pilot school, up to his singular place as the only man to fly on Mercury, Gemini, and Apollo missions. The narrative chokes now and then on needless details--lists of Schirra's awards, lots of Navy cheers and aviator lingo--but provides expected thrills when recounting the space flights, especially the rendezvous between Gemini 6 and 7. Schirra also argues for an orbiting space station, and suggests that NASA might benefit by consulting astronauts more often about engineering problems. Lightweight, amusing portrait of the astronaut as All-American boy.