Air navigation chart V30 (series). 20. Lat 29°N-45°N. long. 118°W-150*W. Scale 1 in.=30 naut. m. (1:2, 188.-800) at lat. 37°30′. contour interval 1000, 2000, 3000, 5000, 7000, 9000 and 12,000 ft.