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Simes is the surname of a pilot on Galactica, third in seniority to Captain Lee Adama and Lieutenant Kara Thrace (TRS: "Fragged").

Given that both his immediate superior, Lt. Thrace, and an inferior, Lt. Joe Palladino are lieutenants, he must share that rank. He is apparently passed over when Commander William Adama assigns a new CAG to replace his son, in favor of the unfortunate George Birch (TRS: "Home, Part I").