Section 147.833 - Na Kika FDS safety zone(a)Description. Na Kika FDS, Mississippi Canyon 474 "A" (MC 474 "A"), located at position 28°31'14.86" N, 88°17'19.69" W. The area within 500 meters (1640.4 feet) from each point on the structure's outer edge is a safety zone. These coordinates are based upon [NAD 83].(b)Regulation. No vessel may enter or remain in this safety zone except the following: (2) A vessel under 100 feet in length overall not engaged in towing; or(3) A vessel authorized by the Commander, Eighth Coast Guard District.CGD08-03-039, 69 FR 21066 , Apr. 20, 2004