Following the container ship PETUJA up the firth today was the Royal Navy's Type 23 'Duke' class frigate SUTHERLAND. Launched by Yarrows at Scotstoun in March 1996, she was commisioned into naval service in July 1997. Likely to be serving with the Royal Navy for a good number of years yet - she is not due to be decommissioned until 2025 - SUTHERLAND was given a multi-million pound refit at Rosyth, which was completed in November 2008. This refit included new sonar equipment and upgrading of her Seawolf missile systems. The refit also included modifications to her stern to improve fuel efficiency, and resulted in challenges being given to other Type 23 ships to see which vessel was fastest.