[1][2] The design chosen, a joint effort by Vickers and John Brown,[a] was of similar layout to the Hawthorn Leslie variant of the M-class destroyer.

[4] The ships were propelled by two geared steam turbines driving two shafts, and fed by four Yarrow water-tube boilerss, giving a distinctive four-funneled silhouette.

[1] In early 1926, Alsedo supported the transatlantic flight from Spain to Buenos Aires, Argentina, of a four-man Spanish Air Force crew led by pilot Major Ramón Franco—the brother of future Spanish caudillo Francisco Franco—and including copilot/navigator Captain Julio Ruiz de Alda Miqueleiz in the Dornier Do J Wal ("Whale") flying boat Plus Ultra ("Farther Still").

The seven-stage journey covered 1,429 miles (2,300 km) nonstop on 30 January 1926 from the Cape Verde Islands to Fernando de Noronha.

To lighten the plane for the third and longest leg of their seven-stage flight, Alsedo transported one of the aviators along the route so that he could meet Plus Ultra when it arrived at Fernando de Noronha.

This resulted in Velasco seeing heavy service, helping to sink the Republican submarine B6 on 19 September 1936, and taking part in the Battle of Cape Palos.