In addition to experimental developments, "Hazelwood" continued to engage in the many duties assigned to a destroyer. As America confronted Russia over the introduction of offensive missiles into Cuba in October 1962, she steamed again to the troubled Caribbean for antisubmarine and surveillance patrols. "Hazelwood" arrived Guantanamo Naval Base 5 November, just after the quarantine of Cuba had gone into effect and remained on guard during the crisis, serving as a Gun Fire Support Ship for Task Force 84. When the nuclear submarine "Thresher" failed to surface 10 April 1963, "Hazelwood" immediately deployed to the scene of the tragedy with scientists from the Woods Hole Oceanographic Institution to begin a systematic search for the missing ship.