HMS Shannon was a 28-gun Coventry-class

Coventry class frigate

These 28-gun sailing frigates of the sixth rate were designed in 1756 by Sir Thomas Slade "to the draught of the Tartar with such alterations withinboard as may be judged necessary"...

 sixth-rate

Sixth-rate

Sixth rate was the designation used by the Royal Navy for small warships mounting between 20 and 24 nine-pounder guns on a single deck, sometimes with guns on the upper works and sometimes without.-Rating:...

 frigate of the Royal Navy

Royal Navy

The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...

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Construction

The Shannon was one of five frigates of the class built of fir rather than oak. Fir was cheaper and more abundant than oak and permitted noticeably faster construction, but at a cost of a reduced lifespan; the four fir-built Coventry-class vessels that did not get captured lasted an average of only nine years before being struck off.