Marines with 2nd Battalion, 1st Marine Regiment, put their thumbs up after securing themselves into an MV-22B Osprey during egress training aboard Marine Corps Base Camp Pendleton, California, Aug. 18. Marines conducted the training drills as part of predeployment training for the 13th Marine Expeditionary Unit. (U.S. Marine Corps photo by Sgt. Lillian Stephens/Released) - Marines with 2nd Battalion, 1st Marine Regiment, put their thumbs up after securing themselves into an MV-22B Osprey during egress training aboard Marine Corps Base Camp Pendleton, California, Aug. 18. Marines conducted the training drills as part of predeployment training for the 13th Marine Expeditionary Unit. (U.S. Marine Corps photo by Sgt. Lillian Stephens/Released)