Abstract: In order to solve the problem of high false alarm rate and low response of aircraft fire detectors,an aircraft fire multi-sensor detection method based on smoke,temperature,CO and CO₂ was worked out and a multi-parameter alarm algorithm was developed.First,suitable detectors were selected to form a smoke,temperature,CO and CO₂ multi-sensor detection device.Then the common fire materials and the nuisance sources were used to carry out true and false fire tests in a simulated cargo.The information on characteristics of fire was extracted from the test data,and a multi-parameter alarm algorithm was developed.The results show that the real fire produces a large amount of CO and CO₂,and their mass concentrations increase greatly,that the false fire produces only a very small amount of CO and CO₂,and the concentrations are almost the same as the environment,that the multi-sensor fire alarm device can accurately distinguish the true from false fire source,and reduce the false alarm rate,and that the multi-parameter alarm algorithm responds to fire faster than the single parameter algorithm.

Key words: aircraft fire detectors, multi-sensor, CO₂ gas concentration, false alarm rate, alarm algorithm