Battle of Installation 05

The Battle of Installation 05, also known as the Battle of Delta Halo, was a major engagement between the United Nations Space Command, Covenant, Sentinels, and the Flood on the Forerunner ringworld Installation 05, otherwise known as "Delta Halo".

Introduction

During the First Battle of Earth, the Prophet of Regret lead a small fleet of two Assault Carriers and thirteen CCS-class Battlecruisers on an expeditionary raid that stumbled upon Earth, the strongest UNSC stronghold planet. After substantial ground, air, and space losses, Regret fled in an Assault Carrier over New Mombasa, opening a Slipspace rift and destroying the city in a devastating Slipspace cataclysm as it initiated an emergency jump to Installation 05, although how the Covenant obtained the coordinates to Installation 05 were unknown.

However, upon Fleet Admiral Terrence Hood's order, five United Nations Space Command Defense Force warships nearby Mombasa were close enough to catch onto the Assault Carrier's rift before it terminated: three UNSC Frigates, the UNSC In Amber Clad, UNSC Paris, and the UNSC Redoubtable, one UNSC Corvette, the UNSC Coral Sea, and one UNSC Prowler, the UNSC Dusk, were able to enter the Slipspace field, trailing the Assault Carrier.

Their shadowing, however, was not exactingly precise. Only the frigate In Amber Clad was successfully trailed the Assault Carrier to Installation 05. The prowler Dusk arrived days later near the Covenant homeworld ship High Charity, and the Coral Sea, Paris, and Redoubtable were not anywhere near the engagement because of the imprecise physics of Slipspace.