Aaah. Air sampling pods, were they. No wonder we could never get a firing solution.
And that's not the only thing 27 inherited from 543; many of the ancient aircrew also moved over. One paricular crew made up entirley of ex-543, with the exception of the co-pilot, who at the ripe age of 45 brought the average crew age down to about 53 (although at the time they looked more like 73). God bless the "Gindits".