Designing of control and expulsion equipment for the pitot-static system of passenger airplanes

The article discusses the issue of automating the serial process of bleeding and control of the pitot- static system of passenger airplanes. A functional diagram and basic design of some parts of the combined equipment are proposed. This equipment makes it possible to alternate the above-mentioned operations with great effectiveness. At the system control stage, the pressure or vacuum in it is created by a pressure-vacuum pneumatic unit. This pneumatic unit consists of a compressor and a set of electromagnetic valves that allow the compressor to be connected to the pumping or scavenging line. The value of the generated pressure is regulated by the flow rate in the pressure/scavenging channel and in the venting channel. Simulation of changes in ambient temperature is achieved due to blowing heated or cooled air over the temperature sensors of the aircraft. Pressure or vacuum in the controlled system is created in turn, in each of its lines. At the expulsion stage, a compressed-nitrogen cylinder acts as the pressure source. The pressurized gas passes through the pitot and is released into the atmosphere, cleaning out the contaminations. No manual operations are required for installing and removing connection hoses after connecting the proposed combined equipment to the pitot-static system. Remote-controlled electromagnetic valves connect the channels of the controlled system to the pressure-vacuum pneumatic unit and the source of compressed nitrogen. This reduces the duration of successive operations for the system’s maintenance.