Ru'swum-pattern Phantom

Were you looking for the Type-52 Phantom seen in Halo 2 and Halo 3?

The Type-44 Troop Carrier, commonly known as the Phantom, is a Covenant dropship manufactured by Achoem Weapons.

Overview
The Type-44 Phantom's prominence was due to its speed, maneuverability, and firepower in atmospheric and exoatmospheric environments. It was later supplanted by a newer model, the Type-52, which was ubiquitous later in the Human-Covenant War. The Covenant remnant use the Type-44 as their primary dropship, likely due to the scarcity of the newer model.

List of appearances

 * Halo 4