Air navigation chart V30 (series). 51. Lat. 0°-15° N. long. 0°-25° W. Scale 1″=30 naut. m. (1:2,188,800) at lat. 7° 30′, contour interval 1,000, 2,000, 3,000, 5,000, 7,000, 9,000 and 12,000 ft.