166 has been active in: In 2004, HMM-166 deployed as the aviation combat element of the 11th Marine Expeditionary Unit in support of Operation Iraqi Freedom.

On 5 November 2007, the squadron deployed to the Western Pacific as the aviation combat element of the 11th Marine Expeditionary Unit.

From 4 to 6 December, as part of the 11th MEU, HMM-166 flew 29 humanitarian assistance missions over Bangladesh to transport more than 54,165 pounds of food and supplies and 1875 gallons of water to the people most affected by Tropical Cyclone Sidr.

[1] On 5 May 2009, a SuperCobra belonging to the squadron crashed at 1154 hrs PST into the Cleveland National Forest, California.

They participated in exercises in East Timor, Indonesia, United Arab Emirates, Kuwait and Djibouti.