Since he had been a frequent correspondent with the Admiralty during the Louisburg campaign, the London sea lords were aware of Pepperrell’s talents and experience. Using Admiral Warren as an intermediary, they wrote to him in late 1746 to ask that he gather materials for and supervise the construction of a new 44-gun Navy frigate to be built in the Piscataqua area. It was one of four new ships to be built for the Royal Navy in the colonies.

In March of 1747, Pepperrell contacted Benning Wentworth in Portsmouth on the matter, and the governor had his suppliers gather the wood, masts, rope, sails, cordage and tons of other items the would need to construct the warship.

Pepperrell supervised the building of the ship in the Piscataqua basin at the Portsmouth shipyard of Nathaniel Meserve, who also had gone to Louisbourg with a New Hampshire regiment and who had solved the problem of getting the guns across the marshes.

Once a week, the Baronet crossed the Piscataqua to inspect the work carefully. When the hull was complete and with only one mast in place, the ship was loaded with spars, yards and everything needed for a proper fitting out. On May 4, 1748, the ship was completed and ready to be sent to England. She was then escorted to England for the rest of the fitting out. The resulting vessel -- America -- had a brief career in the Royal Navy. Well-built, she was known as a good sailing ship, but due to some modifications on her design made by Commodore Charles Knowles, wood was overexposed to the elements and rot set in. Not long after her commissioning, America was condemned and taken out of service.

In an interesting side note, America played host to a unique meeting while it was being built. During the colonial era, the Portsmouth/Kittery region was a center of Freemasonry. Eventually four distinct Masonic lodges -- three in Portsmouth and a fourth in Kittery – were created to handle local membership. Shipbuilder Nathaniel Meserve belonged to the oldest one – St. John’s Lodge in Portsmouth – and he arranged to hold a lodge meeting on board the ship to show it off to members and to use it to recruit new members. It appears it was a well-attended meeting. Although Masonry was popular in the colonies, there is no indication Pepperrell was ever a member.

In spite of the fate of this one vessel, American shipyards continued to produce superior fighting ships, particularly frigates, as evidenced by the performance of the U.S.S. Constitution during the War of 1812.