The Sentry (MCM 3) is the 3rd Avenger-class mine countermeasures ship and the second United States ship to bear that name. The keel was laid down on October 8, 1984, at Peterson Builders in Sturgeon Bay, Wisconsin. She was christened and launched on September 20, 1986; USS Sentry was commissioned on September 2, 1989; Lt. Cmdr. Peter F. Carr in command.

June 6, 1990 The Sentry arrived in Vancouver, B.C., Canada, for a scheduled port visit.

June 1, 1991 Lt. Cmdr. George P. Croy, III relieved Lt. Cmdr. Peter F. Carr as CO of the MCM 3.

August 25, 1992 USS Sentry arrived in its new homeport of Ingleside, Texas, after a transit from San Diego, Calif.

February 16, 1993 USS Sentry, commanded by Lt. Cmdr. Neal J. Kusumoto, departed Naval Station Ingleside for its maiden six-month deployment in the U.S. 6th Fleet Area of Responsibility (AoR).

October 29, 1994 Lt. Cmdr. Terry T. Miller became the 3rd CO of the USS Sentry.

In February 1998, the Sentry participated in a Squadron Exercise 98-1 with the USS Defender (MCM 2), USS Robin (MHC 54) and USS Black Hawk (MHC 58).

August 6, 1999 Lt. Cmdr. Donald G. Hornbeck relieved Lt. Cmdr. George Bonsall as the 9th commanding officer of Sentry.

March 16, 2000 USS Sentry departed Ingleside, Texas, for Caribbean Sea operations as component of Mine Warfare Readiness Group (MIWRG) 1 and a Great Lakes Domestic Outreach Recruiting Cruise 2000.

May 22, 2002 The Sentry recently arrived in New York City, N.Y., to participate in annual Fleet Week celebration.

December 6, Lt. Cmdr. John M. Zuzich relieved Lt. Cmdr. Frank S. Linkous as CO of the MCM 3.

January 13, 2003 USS Sentry departed homeport for a surge deployment in support of the Global War on Terrorism, as part of the Mine Readiness Group (MRG) 3.

April 27, The mine countermeasures ship pulled into Valletta, Malta, for a liberty port visit.

October 8, 2004 Lt. Cmdr. Patrick T. Britt relieved Lt. Cmdr. Lt. Cmdr. John M. Zuzich as the 12th CO of USS Sentry.

September 21, 2005 The Sentry moored outboard the USS Scout (MCM 8) and USS Qarrior (MCM 10), in a modified moor of five MCM ships at Ingleside Turning Basin-Nest, in preparation for Hurricane Catrina.

April 16, 2007 Lt. Cmdr. Benjamin R. Nicholson relieved Lt. Cmdr. John K. Reilley as the 16th commanding officer of MCM 3.

September 9, 2009 USS Sentry, commanded by Lt. Cmdr. Hans E. Lynch, arrived in its new homeport of Naval Base San Diego in San Diego, Calif., in accordance with the Defense Base Relocation and Closure Commission.

June 23, 2012 USS Sentry arrived in Manama, Bahrain, aboard the M/V Tern, after a 45-day transit from Long Beach, Calif., for a seven-month deployment in the U.S. 5th Fleet Area of Responsibility.

August 29, The Sentry is currently participating in a mine countermeasure exercise in the Arabian Gulf.

September 20, MCM 3 recently departed Mina Salman Port in Manama to participate in International Mine Countermeasures Exercise (IMCMEX) 2012.

May 13, 2013 USS Sentry departed Manama to participate in at-sea phase of International Mine Countermeasures Exercise (IMCMEX) 2013.

November 1, 2014 The Sentry recently departed homeport to participate in IMCMEX 2014; Completed INSURV inspection on Feb. 10, 2015.

April 19, USS Sentry, along with the USS Dextrous (MCM 13), recently arrived in Gulf of Aden to increase the naval presence in response to current instability in Yemen; Transited the Bab el-Mandeb Strait nortbound, in support of Operation Decisive Storm on April 28.

May 19, The Sentry recently moored outboard the USS Dextrous at Tanker Berth 10 in Port of Djibouti for a brief stop to refuel.

December 16, Lt. Cmdr. Lawrence Heyworth, IV relieved Lt. Cmdr. Janice A. Pollard as CO of the USS Sentry during a pierside ceremony at Mina Salman Port.

April 10, 2016 USS Sentry departed Manama to participate in at-sea phase of International Mine Countermeasures Exercise (IMCMEX) 2016.

May 31, The Sentry recently departed homeport to participate in annual training exercise Poseidon Assurance, with the USS Gladiator (MCM 11), HMS Middleton (M34) and USCGC Maui (WPB 1304); Participated in a joint mine countermeasures exercise SQUADEX-16 from July 30- Aug. 5.

April 13, 2017 USS Sentry moored at Berth 3, Sultan Qaboos Port in Muscat, Oman, for a three-day port call.

May 15, USS Sentry moored at Mina Salman Port in Manama following a two-month patrol.?

From August 8-10, the Sentry participated a training exercise Spartan Kopis 17-2, with the USS Hurricane (PC 2), USS Thunderbolt (PC 12) and USCGC Aquidneck (WPB 1309), while underway in the Arabian Gulf.

September 12, USS Sentry participated in a photo exercise (PHOTOEX) with the HMS Bangor (M109), HMS Ledbury (M30) and RFA Cardigan Bay (L 3009), while underway off the coast of Bahrain, at the start of a combined U.S./U.K. mine countermeasure exercise (MCMEX) 17-3.

May 22, 2018 USS Sentry completed a 10-day Mine Warfare (MIW) Surface Warfare Advanced Tactical Training (SWATT) exercise, with embarked mine warfare trainers, while underway in the Arabian Gulf.

June 12, The Sentry recently departed Manama to participate in a combined U.S./U.K. mine countermeasure exercise (MCMEX) 18-2.

September 10, USS Sentry participated in a PHOTOEX with the HMS Brocklesby (M33), HMS Shoreham (M112) and two U.S. Coast Guard ships, while underway off the coast of Bahrain, at the start of a combined U.S./U.K. mine countermeasure exercise (MCMEX) 18-3.

April ?, 2019 USS Sentry departed homeport to participate in a mine countermeasures exercise Artemis Trident 19; Participated in a combined U.S./U.K. mine countermeasure exercise (MCMEX) 19-2 from June 10-20.

July 6, The Sentry participated in a PHOTOEX with the USS Mason (DDG 87), USS Devastator (MCM 6), USS Gladiator (MCM 11) and USS Dextrous (MCM 13), while underway off the coast of Bahrain; Transited the Strait of Hormuz southbound on July 9; Inport Muscat, Oman, in mid-July.

April 15, 2020 Lt. Cmdr. Franklin Lemene relieved Lt. Cmdr. Cameron J. Burnette as commanding officer of the MCM 3.

February 5, 2021 USS Sentry is currently moored at Berth 14, Mina Salman Port in Manama, Bahrain; Underway again on Feb. 14; Participated in exercise Khunjar Hadd 26, while underway in the Gulf of Oman, from Feb. 21-25.

April 20, The Sentry recently departed homeport to participate in a mine countermeasures exercise Artemis Trident 21.

June ?, Lt. Cmdr. Tyree D. Barnes relieved Lt. Cmdr. Franklin Lemene as CO of the USS Sentry during a change-of-command ceremony in the ship's pilot house at Mina Salman Port.

October 16, USS Sentry moored outboard the USS Gladiator in Port of Djibouti for a one-day stop to refuel; Transited the Bab el-Mandeb Strait northbound, escorted by USS O'Kane (DDG 77), on Oct. 18; Inport Djibouti again on Oct. 30.

November 16, USS Sentry moored at Berth 15, Mina Salman Port in Manama following a six-week patrol.

October 6, 2022 Lt. Cmdr. Daniel J. Pedrotty relieved Lt. Cmdr. Tyree D. Barnes as CO of the Sentry during a change-of-command ceremony on Naval Support Activity Bahrain.

February ?, 2023 USS Sentry undocked from a floating dry-dock, at BASREC shipyard in Manama, and moored at Mina Salman Port.