Nassco was contracted by APT to design and construct five 50,000 deadweight tonne (dwt), liquified natural gas (LNG) conversion-ready product carriers with a 330,000 barrel cargo capacity.
The ECO Class tanker, christened as Magnolia State, is a 610ft long vessel featuring the new ECO design, which will provide an improvement in fuel efficiency.
General Dynamics NASSCO president Fred Harris said: "The revolutionary ECO Class provides our customers with an alternative option for transporting product that is cost-effective and friendly to the environment.
"Like the Magnolia State, each ship designed and constructed at NASSCO is built with pride and ownership. Our shipbuilders know they’re not just building a product tanker; they’re building a vessel that helps fuel our economy."
Kinder Morgan Terminals vice-president and American Petroleum Tankers president Robert Kurz said: "We look forward to taking delivery of our second ECO Class tanker from NASSCO.
"This is another example of American Petroleum Tanker’s commitment to building our fleet and servicing our customers. And we thank NASSCO for their continued support which paved the way for this important milestone to be achieved."
In 2014, Representative Scott Peters signaled the start of construction of the Magnolia State. In June 2015, California State Assemblywoman and former speaker Toni Atkins laid the keel.
Construction and operation of the new ECO Class tankers are according to the Jones Act, which requires vessels carrying cargo between US ports to be constructed in US shipyards.