[a] Naval historian Rif Winfield quotes her burthen as 68414⁄94 tons with a length at the gundeck of 122 feet 6 inches (37.3 m) and beam of 34 ft 10 in (10.6 m).

[2] Grand Duchess of Russia departed for Boston, Massachusetts carrying 150 marines on 30 March 1775 and she remained in North American waters for the next two years.

Vice Admiral Lord Howe, commander of the North American Station, informed the Admiralty on 23 April that he had purchased the Grand Duchess of Russia and commissioned her as HMS Vigilant to bombard targets ashore.

[3] Her conversion was completed by the end of June and her first task was to cover the evacuation of British troops from Perth Amboy, New Jersey on 29 July.

The following month, Vigilant served as Howe's flagship when he landed British troops at Elkton, Maryland, at the northern end of Chesapeake Bay, during the Philadelphia Campaign.

The ship accompanied the British squadron to Newport, Rhode Island as it attempted to lift the Franco-American siege, but Vigilant was badly damaged when a storm interrupted the planned battle on 13 August.

Despite the damage, she supported British troops on 29–30 August as they pursued the retreating Americans who had abandoned the siege after the French ships sailed to Boston for repairs.

Lacking substantial repairs during this time, the ship's condition deteriorated until her crew refused to take her to sea from Beaufort, South Carolina on 28 February 1780 to support the planned siege of Charleston.