From Halopedia, the Halo wiki
Lieutenant Commander Gail Purdy (service number 63673-45327-GP) was a Senior Officer in the UNSC Navy. She was assigned to the UNSC Pillar of Autumn as Chief Engineer. LCDR Purdy was middle aged and stout, with ginger-colored hair and stern and serious eyes.
Purdy was aboard the Autumn when it arrived at Installation 04. Presumably, she took a Bumblebee life pod to the surface when the vessel crashed. At Alpha Base, she managed to survive until the very end of the event. She was one of the few specialists that was assigned guards during the ODST attack on the Truth and Reconciliation. She pointed out a conduit to McKay that she knew was vital to the function of the ship. McKay ended up destroying that very piece of technology to stop the Flood from getting to Earth.
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