Published by the Army Air Forces Training Command Visual Training Department, from technical material furnished by the Army Air Forces Instructors School (Navigator), Selman Field, Monroe, Louisiana. To be used in conjunction with current AAF Training Command memorandum covering Advanced Navigation Training. This textbook was used to teach advanced navigation at San Marcos Army Air Field in 1944 and 1945. It is extensively illustrated with diagrams to explain virtually all material covered in the text.