Hocus

Hocus was a Pelican pilot in the UNSC Navy during the Second Battle of Earth. She was stationed at the UNSC Crow's Nest base, before being stationed aboard the UNSC frigate  UNSC Forward Unto Dawn, piloting Pelican Kilo 023. When flying from Crow's Nest, she rescued the Master Chief who was pinned down by a couple of phantoms after rescuing Sergeant Johnson and a squad of captured marines. Hocus participated in numerous ground insertions during the Battle of the Ark, including a mission to deactivate the barriers of the Ark's control room.

It is unknown if she died or not, since the game did not mention her after the level, The Covenant. It is likely she survived and was returned to Earth along with the rest of the remaining humans and Elites stationed over Installation 00.

Trivia

 * Hocus has a very similar role to that of Foehammer, a Pelican pilot in the Halo: CE game.
 * Using a glitch in the last level of Halo 3 will cause Johnson to sometimes yell "I did this for Hocus!" This may suggest a relationship between the two.
 * Viewing the level Sierra 117 through the theater you can enter the cockpit of the pelican (by going through the hatch and then through the door to the cockpit) to see that the bodies piloting the pelican are male despite Hocus being female. This probably means that she survived.