Air navigation chart V30 (series). 28. Lat. 14° N-30° N, long. 129° E-101° E. Scale 1 in.=30 naut. m. (1:2.188.-800) at lat. 22°30′, contour interval 1,000, 2,000, 8,000, 5,000, 7,000, 9 000 12,000, 15,000, and 20,000 feet.