The Crockett was designed for the roles of coastal patrol, blockade reconnaissance and support missions. She took part in operations during the Vietnam War. Her primary duties were in "Operation Market Time". The objective of these missions was to prevent the Viet Cong from using the coastal waters to transport weapons and supplies. When boats were spotted, she would go into high-speed pursuit and once she was among them, runabouts with outboard engines would be lowered over the side and two or three man crews would round them up.

During a patrol at SEA FLOAT, CROCKETT came under fire from a VC ambush. Four rockets were fired at her starboard side, with two causing no damage. The third rocket exploded when it hit a lifeline by the 3"/50 gun mount, wounding two crewmen. One crewman was Med-evaced and received the Purple Heart, while the other was treated with first aid on the scene.

The fourth rocket turned out to be one of the luckiest shots ever taken! It detonated in the compartment forward of the Chiefs quarters, blowing up the 220 volt control box for the 3"/50 gun mount. CROCKETT Commanding Officer brought the ship to a stop while the crew retaliated with every available gun blazing away. The damage control crew quickly brought the fire under control. CROCKETT returned to Cam Ranh for repairs and was back in the river within days of the attack.

  She was ultimately stripped of her gas turbine and armament and transferred to the Environmental Protection Agency and renamed the Rachel Carson. Unfortunately the USS CROCKETT (Rachel Carson) has been scrapped, this was according to Mr. Ed McLean at the Environmental Protection Agency.