General Dynamics NASSCO on Thursday delivered Magnolia State, the second of five LNG-conversion-ready 50,000 dwt Jones Act tankers the shipyard is building for Kinder Morgan subsidiary American Petroleum Tankers (APT).

The five 610 ft ships in the APT contract have a 330,000 barrel cargo capacity and are being built to a new "ECO" design by DSEC, a subsidiary of Daewoo Shipbuilding & Marine Engineering (DSME), that is  33 percent more fuel efficient than product tankers built only a few years ago.

Fuel efficiency concepts include a G-series MAN B&W slow-speed main engine and an optimized hull form. The tankers also have dual-fuel-capable auxiliary engines and the ability to accommodate future installation of an LNG fuel-gas system.

The Magnolia State and other ECO Class ships are the first in the Jones Act fleet with a PMA+ Notation from ABS, signifying compliance with one of the highest standards of human factors in engineering design. The PMA+ notation is created to facilitate safe access to vessel structure and spaces in ways that are rooted in the fundamentals of human ergonomics.