The Navy has finished upgrading the Aegis Weapon System for two destroyers that give the ships the capability of carrying out in-theater air fighting as well as taking out ballistic missiles, the Navy said Monday.

The Navy said the milestones were completed on the Arleigh Burke-class (DDG-51) destroyers, the USS Barry (DDG-52) and USS Benfold (DDG-65). Both vessels are expected to return to the fleet early next year, Naval Sea Systems Command said.

A key centerpiece of the modernization, called Aegis baseline 9, is the installation of a multi-mission signal processor (MMSP) that give the ships the capacity to carry out in-theater air combat missions as well as the ballistic missile defense missions.

The Barry and Benfold each underwent successful sea trials to demonstrate the new capability, NAVSEA said. Lockheed Martin [LMT] is the prime contractor for Aegis.

“These upgrades to major shipboard systems on DDG-51-class ships strengthen the Surface Fleet by improving the ships’ capability to tackle missions and engage evolving threats,” said Capt. Ted Zobel, NAVSEA’s program manager for surface combatant modernization.

The ships also received the real time information sharing cooperative engagement capability (CEC), anti-submarine warfare upgrades and improvements to the MK 45 five-inch gun, NAVSEA said.