Construction of the US Navy’s San Antonio-class amphibious transport dock, Harrisburg, has started and was officially marked with a ceremonial authentication of the keel.

The ceremony was held at Huntington Ingalls Industries’ (HII) Ingalls Shipbuilding division.

Also called landing platform dock (LPD), Harrisburg (LPD 30) has been named after the city of Pennsylvania.

Harrisburg will be the first Flight II LPD and the 14th San Antonio-class ship of the US Navy.

According to the company, the next generation LPD Flight II amphibious ships will replace two classes of dock landing ships, Whidbey Island (LSD 41) and Harpers Ferry (LSD 49) .

During the ceremony, initials of the ship’s sponsor, Alexandra Curry, were welded onto a plate.

Ingalls Shipbuilding president Kari Wilkinson said: “While she could not join us, we welcome Curry in spirit as she is now an important part of our shipbuilding family.

“We look forward to being with her throughout the life of the ship, and we are very grateful for her commitment to this crew. She is a true patriot, with deep respect and gratitude for military service.”

The San Antonio-class ships are 684ft-long, 105ft-wide and designed to meet the various amphibious and expeditionary mission requirements of the navy and Marine Corps.

Currently, Ingalls Shipbuilding is constructing three more San Antonio-class ships. So far, it has delivered 11 vessels of the class to the navy.