Development and Application of a Real Time Bleed Air Contamination Monitor

The bleed air contamination monitor was developed at Honeywell to ensure that our products provide the highest quality bleed air to aircraft environmental control systems. The bleed air contamination monitor is currently for ground based applications only. It is being developed into an on board system for future applications.

Current Aircraft Cabin Air Quality measurement techniques are very labor intensive and require days or even weeks of laboratory analysis to provide results. This is unacceptable from a manufacturing and service perspective. Development of a real time analyzer began in the early 1990s and has progressed to a point where a product is ready for introduction that not only provides real time information regarding engine air contamination, but is also easy for operators to use with a minimum amount of training. It will allow line maintenance supervisors to quickly assess the condition of bleed air from individual engines and APUs without having to remove them from the aircraft and send them to an overhaul shop for inspection and tear down.

The instrument output is versatile and can be configured to provide either a graphic type of display or a data reduction yielding a quantitative amount of contamination in the bleed air supply compared with that in the engine inlet.

This device can not distinguish between types of fluid, and therefore must rely on some operator knowledge of the system to determine sources of contamination. It is anticipated that in the future other sensors will be incorporated within the measurement system that will be able to positively identify the source of contamination within the environmental control system.