An Air Station Houston MH-65 Dolphin helicopter aircrew medevacs a 49-year-old crew member from a chemical tanker near Freeport, Texas, May 11, 2018. Coast Guard Sector Houston-Galveston watchstanders received a request from the captain of the 580-foot vessel Stolt Perseverance for the medevac of a crew member who was reportedly burned by venting steam aboard the chemical tanker 48 miles offshore. U.S. Coast Guard video by Air Station Houston.