Aircraft Air Quality and Bleed Air Contamination Detection

FAA Technical Libraryhttps://doi.org/10.21949/15244792022PDFTech ReportJones, Byron WKansas State UniversityUnited States. Department of Transportation. Federal Aviation Administration. William J. Hughes Technical CenterUnited States. Department of Transportation. Federal Aviation Administration. William J. Hughes Technical CenterUnited StatesAir qualityAircraft cabinsConcentration (Chemistry)ContaminantsMeasurementBleed AirDOT/FAA/TC-21/45693KA9-20-P-00033Final ReportThe purpose of this project was to provide a data-driven process to identify sensing technology with good potential for detecting bleed air contamination from engine oil, hydraulic fluid, or deicing fluid. Reports from major aircraft cabin air studies were reviewed to identify the range of constituents that can be expected in cabin air, especially as they pertain to the aforementioned contaminants and their potential markers. One of the projects was the National Aeronautics and Space Administration Vehicle Integrated Propulsion Research (NASA-VIPR) project where controlled amounts of engine oil were injected into the engine compressor of a C-17 transport aircraft and the resulting contaminants in the bleed air measured. Three additional cabin air quality studies conducted on revenue flights were reviewed. These three studies provide data for a combined total of 249 flights on a variety of makes and models of aircraft. These studies provide adequate documentation of typical aircraft cabin air. Information from this review was used to identify potential markers of the bleed air contaminants. Additionally, collaboration was established with several technical committees from the Society of Automotive Engineers (SAE), American Society of Heating, Air-Conditioning and Refrigerating Engineers (ASHRAE), and American Society for Testing and Materials (ASTM) and with project personnel from the prior European Union Aviation Safety Administration (EASA)-funded cabin air study. Key objectives of the project were to identify sensors and sensing technology with potential for detection of one or more of the three aforementioned bleed air contaminants and to develop a plan for test stand engine experiments to evaluate the sensors with controlled amounts of the three contaminants. Sensors and instruments were identified and a test plan was developed. Additionally, through the collaboration with ASHRAE 1830 and the support of the industry working group, many of the experiments identified in the test plan were completed. The analysis of the data from these experiments is ongoing and will be reported in the ASHRAE 1830 project report. However, preliminary assessment of the sensing technology has been possible.137