The engines were designed to produce a total of 16,500 indicated horsepower (12,300 kW) which was intended to give a maximum speed of 25 knots (46 km/h; 29 mph).

[2] When Sentinel ran her sea trials, she reached a speed of 25.1 knots (46.5 km/h; 28.9 mph) from 16,433 ihp (12,254 kW) for eight hours.

[3] The Sentinel-class cruisers carried enough coal to give them a range of 2,460 nautical miles (4,560 km; 2,830 mi) at 10 knots (19 km/h; 12 mph).

[9] After another refit in 1912 at HM Dockyard, Devonport, Sentinel was assigned to the 3rd Light Cruiser Squadron in 1913 for the annual manoeuvres and was then transferred to lead the 9th Destroyer Flotilla at Portsmouth.

In 1915 she was temporarily assigned with 6th Light Cruiser Squadron in the Humber to defend against Zeppelin raids, before she was transferred to the Mediterranean and then to the Aegean in 1918.

Later that year, Sentinel was part of the squadron sent through the Dardanelles to undertake duties in the Black Sea, where Britain was becoming involved in the Russian Civil War.