HMS Blazer is an Archer-class patrol vessel of the Royal Navy. She was built by Vosper Thornycroft. She is 20.8 metres (68 ft 3 in) long and 5.8 metres (19 ft 0 in) wide and powered by two Rolls-Royce diesel engines. The ship is based at HMS Nelson, the shore base in Portsmouth and was commissioned in 1988. Blazer carries a crew of four, plus a commanding officer. A training officer accompanies up to 10 students when Blazer is operating in its URNU capacity. The ship is affiliated to both the Southampton University Royal Naval Unit (SURNU) and Portsmouth University Royal Naval Unit.