The article provides a comparative analysis of the provisions of the 1919 Convention on the Regulation of Aerial Navigation and the 1944 Convention on International Civil Aviation. The analysis identified imperfections of the 1944 Convention still remaining the major international legal act on the regulation of air navigation processes. It is proposed recommendations to improve key areas of international air law regulation. Special attention is paid to the activities of the International Civil Aviation Organization (ICAO) in the development of draft international treaties, adoption of standards and recommended practices aimed at unifying national air laws establishing permits for aircraft to enter other states and regulate the procedure of designation prohibited and dangerous zones. In consequence of the comparison difference in the legal status of annexes to both Conventions mentioned is established. The problems of the international legal classification of aircraft, the legality of the use of weapons against civil aircraft that violate the state border or used for illegal purposes that are incompatible with the provisions of the 1944 Convention are analyzed in details. The facts of the realization by coastal states of jurisdiction in air navigation in the flight information areas established on the basis of the relevant regional treaties, have been studied as the confirmation of the international legal custom. The article contains recommendations for all users of the airspace to creation of a common international legal regime of flights of aircraft, rocket launches, guided missiles, ascents and descents of space objects. It is substantiated a necessity of determining international legal responsibility of states for damage caused as a result of an illegitimate act in relation to civil aviation, by amending the 1944 Convention on International Civil Aviation. It is described possible international legal procedures for interaction between search and rescue and air navigation services of the states realizing jurisdiction outside sovereign territories, and makes the suggestions to bring them in line with practice of relief operations on the sea. Also the article focuses on analyzing issues of international legal regulation of investigations of accidents and incidents aimed at identifying true causes of the incident and communicating results of investigations to air transport operators and aircraft manufacturers to prevent similar catastrophes in the future.