Drifters were robust boats built, like trawlers, to work in most weather conditions, but designed to deploy and retrieve drift nets.

[1] Shipyards used to building fishing trawlers or drifters could easily switch to constructing naval versions.

[1] During 1917, a fleet of British drifters, escorted by destroyers and light cruisers, maintained a blockade of the 72 km (45 mi) wide Strait of Otranto, denying the Austro-Hungarian Navy access to the Mediterranean.

[2] Some drifter crews chose to fight, and the Gowan Lee returned fire on the Austro-Hungarian ships.

[3] The lack of sufficient Allied escorts forced the withdrawal of the remaining blockading ships, although only for a short time.