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United Nations Space Command
Sergeant Alasdair R. Schicker (SecNet username: GLancer) was a soldier in the UNSC. He serviced UH-144 Falcons on Reach.
Sometime after the Fall of Reach, the Office of Naval Intelligence launched an investigation of a SecNet message exchange between Schicker and SGT Joseph M. Poteet to determine whether he had inadvertently leaked classified information, including the location of Reach, to the Covenant. The man receiving the information was dubbed "Yuma".