US-based shipyard General Dynamics NASSCO signaled the start of construction of a fourth ”ECO” tanker to be built for American Petroleum Tankers at a steel cutting ceremony Friday, May 8, at its San Diego shipyard.

Each of the five 50,000dwt product carriers to be constructed for American Petroleum Tankers by NASSCO will be LNG-conversion ready and will carry 330,000 barrels of cargo.

With a specialized ECO design, the tankers are more energy efficient and incorporate environmental protection features, including a Ballast Water Treatment System, says the shipbuilder.

NASSCO began construction on the first tanker under the current contract in September 2014.

The construction and operation of the new vessels are aligned with the Jones Act, requiring ships carrying cargo between US ports to be built, crewed and owned by the US.