From Halopedia, the Halo wiki
During the Blooding Years he served aboard the Unflinching Resolve as the navigation officer. During the assault on Vadam the ship took a round that caused the ship to lose its navigation controls. Dunil tried to repair them, but was unable to and informed Avu Med 'Telcam that they were lost. Raia 'Mdama asked him if they would crash, he thought they would, he told her to take cover in the event they did. After the ship suffered a direct hit it crashed on a beach. Dunil survived and helped Raia escape from the ship, then once again from hostile forces. After she was ready to fight, Dunil told her the intelligent thing to do would be to retreat and return with a greater force, to which she agreed. They were about to retreat when allied ships arrived to help.
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