ABOUT THE TRANSITION TO QNH PRESSURE IN THE RUSSIAN FEDERATION

Abstract

This article discusses the advantages and disadvantages of transition to QNH pressure. The analysis of various factors affecting the flight safety has been conducted. A comparative analysis of the two types of altitude reading while approaching the airport has been carried out. The first type is the altitude reading relative to the airfield when at an aerodrome surface an altimeter altitude is equal to zero. This pressure is called QFE. The second one is estimated relatively to the sea level; in this case the aerodrome elevation must be taken into account. Such pressure is called QNH. These both pressures are used in aviation. Historically, QFE pressure was used in the USSR, and after the disintegration of the Soviet Union this type of pressure was used during takeoff and landing. In the mid - 2000s, the majority of Russian airlines began to use the foreign aircraft, mainly the airplanes produced by Boeing and Airbus Companies. Since these aircraft are produced in Western countries, they use QNH pressure, so there are some difficulties of correct altitude setting while approaching an aerodrome, this causes an aircraft descent below the level prescribed by STAR, consequently, decent below minimum safe altitude. The conclusion of necessary transition to QNH pressure was made using the example of aircraft. The article also explains why the transition to QNH pressure flights in the Russian Federation is a top priority and a necessary step for maintaining proper level of flight safety.