PEARL HARBOR (January 8, 2023) The crew of the Los Angeles-class attack submarine USS Chicago (SSN 721) pose with the Battle Efficiency, or Battle "E", pennant January 8, 2023. The Battle “E” award recognizes crews with high levels of sustained proficiency and readiness to perform in an operational environment throughout a year-long evaluation. (U.S. Navy photo by Mass Communication Specialist 1st Class Scott Barnes)