170908-M-CK339-024 U.S. 5TH FLEET AREA OF OPERATIONS (Sept. 8, 2017) Marines with the 15th Marine Expeditionary Unit’s (15the MEU) Combat Cargo, attach an RQ-21A Blackjack skyhook recovery system to a CH-53E Super Stallion helicopter during an external lift aboard the amphibious transport dock ship USS San Diego (LPD 22) in support of exercise Alligator Dagger 2017. Alligator Dagger is a dedicated, unilateral combat rehearsal led by Naval Amphibious Force, Task Force 51, 5th Marine Expeditionary Brigade, in which combined Navy and Marine Corps units of the America Amphibious Ready Group and embarked 15th Marine Expeditionary Unit are to practice, rehearse and exercise integrated capabilities that are available to U.S. Central Command both afloat and ashore. (U.S. Marine Corps photo by Lance Cpl. Jeremy Laboy/Released)