Astronomical navigation is the science of determining the occupation of the ship by observing the celestial bodies. The Nautical Almanac is an annual publication that provides information on the position of celestial bodies or their coordinates. The most famous is British publisher Brown, Son & Ferguson LTD. Brown's Nautical Almanac. The Croatian Nautical Almanac came out as a transcript of The Nautical Almanac from 1996 to 2002. A special „Thanks“ to Professor PhD Petru Čumbelić, Croatia can boast its Nautical Almanac, which is used on all the seas of the world because it is similar to the famous The Nautical Almanac, and contains all the information about the stars and planets that are essential to astronomical navigation. Dr. Petar Čumbelić has developed a program that has enabled the Republic of Croatia to issue a Nautical Almanac. In our Almanac we find all the data as well as in The Nautical Almanac, except that our Nautical Almanac is bilingual, all the names of the moon and stars or ephemeris points important for astronomical navigation are in Croatian as well as in English. Avio tables are the tables used to get the boat position faster by astronomical navigation methods. It consists of six volumes, each containing two zones of eight degrees of latitude with overlap of one degree between the volume.