Some of them really have an inoperative radio, and some just aren't following the arrival procedure properly. In either case, if they're not talking to somebody, there's a very good chance they'll land on the first runway they see, which is 9. That's a bad thing with a stream of traffic landing on 27. N.D. The team works the shift from 0630 to 1300, then a new team of four takes over. They travel on the Friday before the show and train on Saturday.
Training mostly consists of learning the traffic patterns and the special reduced-separation rules.
The team of four rotates positions to keep everybody alert. First the approach spotter calls out the color and type of the approaching airplane. Next the radio person gives the traffic instructions. Then another spotter verifies the wing-rock acknowledgment as the airplane passes over Fisk. Each job requires a different talent.