The Sailfishes were initially equipped with large BPS-2 and BPS-3 radars in and aft of the sail.

They were designed under project SCB 84 for a high surface speed; however, their speed achieved was not significantly faster than converted World War II radar picket submarines.

This class was an attempt to improve on the speed and surfaced seakeeping qualities of the converted World War II submarines previously used as radar pickets.

[2] Despite a 6,000 shp (4,500 kW) diesel plant, their surfaced speed was only a few knots more than the effective speed of their smaller predecessors, so they were incapable of effectively escorting carrier task forces.

In 1964-66 they were modernized under the FRAM II program, with Salmon temporarily receiving Regulus missile guidance equipment.