Battle group

A Battle Group is a UNSC designation for a force of ships that is smaller than a Fleet. A Battle Group is roughly equivalent to a Covenant Task Force in terms of number of ships, however, Covenant ships are far superior to the UNSC's own.

A Battle Group is usually commanded by an Admiral, and each Battle group is assigned a number. When the number is not known, the Battle Group is referred to simply by its flagship. Battle Groups are also created on a temporary basis, with a specific mission or to accomplish a specific task.

Known Battle Groups

 * Sixth Battle Group
 * Battle Group Stalingrad
 * Sol Defense Group 3/A-5

Trivia
The funding the Spartan II program, plus their MJOLNIR Armor and training cost as much as a Battle Group.