22nd Tactical
From Halopedia, the Halo wiki
The Twenty-Second Tactical was a UNSC Marine Corps unit stationed aboard the UNSC Pillar of Autumn.[1]. It was to rendezvous with the Fourteenth Platoon at Bulkhead Charlie 14 aboard the Pillar of Autumn during the Covenant boarding action. Under the Command of Major Antonio Silva, On Captain Keyes order, they HEV'd out of the UNSC Pillar of Autumn.[2] and Onto the surface of Halo 04