RNLB Duncan was the first RNLI lifeboat placed on station in the English coastal town of Sheringham in the county of Norfolk, United Kingdom.

Henry Upcher came to an agreement to provide land at East Cliff, opposite a coal yard for the construction of a lifeboat station.

Funding for the new lifeboat was provided from the gift of Mrs Agnes Fraser (née Duncan)[8] and was made in the memory of her father and uncle.

The private lifeboat Augusta which also served the town at this time was much lighter which gave her an advantage when launches were required in inclement weather.

Despite here grounding the RNLI's report on the rescue it was stated The behaviour of the lifeboat amidst the heavy breakers elicited the admiration of her crew, who expressed the greatest confidence in her.

[8] The Duncan's last successful service took place on 6 December 1882[8] when she was launched in response to a distress signals sent out by the Swedish barque Caroline who was on her way from Hull to Trelleborg.

The Caroline had lost her sails and spar in the heavy weather and together the two lifeboats escorted the barque to Grimsby arriving there the following day.

A request was formulated and sent to the RNLI asking for a new lighter boat with a longer keel and wider beam that would be more suitable for the difficult launch situation in the town.