Ingalls Shipbuilding delivered the sixth National Security Cutter to the Coast Guard and launched the seventh in the past few days, as the now planned nine-ship class continues to grow.

Munro (WMSL-755) delivered on Dec. 16 and will be commissioned in Seattle on April 1, 2017, according to an Ingalls Shipbuilding news release. Kimball (WMSL-756) launched the following day and is set for christening on March 4 and delivery in 2018.

“This is an important milestone for Kimball and the National Security Cutter program,” Ingalls Shipbuilding President Brian Cuccias said in a news release.

“The hot NSC production line we have at Ingalls, with six ships delivered and two more under construction, is allowing us to build these highly capable ships in the most efficient and cost-effective manner possible.”

The eighth ship in the class, Midgett (WMSL-757), is under construction at Ingalls and set for a 2019 delivery. In Fiscal Year 2016 lawmakers funded a ninth ship even though the Coast Guard hadn’t requested to expand the Legend-class National Security Cutter fleet. Lawmakers have considered adding funding for a tenth ship as well.

The Coast Guard had planned to replace 12 Hamilton-class high-endurance cutters with eight NSCs, which are 40 feet longer, have more sophisticated Command, Control, Communication, Computers, Intelligence, Surveillance and Reconnaissance (C4ISR) equipment, and have added small boat and aviation operations capabilities.

The sixth ship is named after Signalman First Class Douglas Munro, the Coast Guard’s sole recipient of the Medal of Honor, according to the Ingalls news release. He was mortally wounded on Sept. 27, 1942, while evacuating a detachment of Marines from Guadalcanal.

The seventh ship is named after Sumner Kimball, who organized and directed the U.S. Life Saving Service, which eventually became the U.S. Coast Guard.