Alarm logical designing method for airplane engine cabin fire alarm detecting system

Abstract

The invention belongs to the field of navigation, and particularly relates to an alarm logical designing method for an airplane engine cabin fire alarm detecting system. A fireproofing controller reads the state of a dual-circuit fire alarm detector according to the time interval between 100 and 1,000ms, performs logical judgment, and sends a judgment result to the alarm system; system omission can be reduced when the false alarm rate of the system is reduced through distribution of the dual-circuit fire alarm detector by combining with a set alarm logic; and especially when any one path of the fire alarm detector sends a fire alarm but the other path does not give out a response, the judgment logic is set to be in a state of prompting flight crew to pay attention on observing the corresponding engine state, so that intense fire which is out of control and is caused by early soft fire happening in the engine cabin due to waiting is prevented if the engine cabin is really ignites or overheats, and delay of an extinguishment opportunity and great loss of life possession can be prevented.

Description

technical field [0001] The invention belongs to the field of aviation, in particular to an alarm logic design method for an aircraft engine compartment fire detection system. Background technique [0002] The engine compartment of the aircraft may be on fire due to severe wear of the machine parts, fuel leakage, electrical fire and other reasons; if it is not controlled in time, it may endanger flight safety and cause disastrous consequences. [0003] The function of the aircraft engine compartment fire detection system is to detect a fire in the engine compartment and notify the crew in time. Aircraft engine compartment fire detection system is mainly composed of three parts: fire detector, fire controller and alarm system. [0004] Most modern aircraft use pneumatic fire detectors with high reliability, good maintainability and easy self-detection function, which surround the surface of the engine compartment body or inside the fire zone to detect fire or overheating in t...

AI Technical Summary

Problems solved by technology

At present, a common alarm logic design method for most aircraft engine compartment fire detection systems in the world is to adopt the layout design of parallel double loops (that is, the A and B two fire alarm detectors are arranged in parallel but independent of each other). When any one of the fire detectors of A and B alarms and the other does not respond, a time limit of 15s is set, and the fire alarm controller conducts a self-test on the unresponsive one. The fault of the fire detection system that does not respond to the detection is due to the power supply If the failure, signal transmission failure or fire detector’s own failure is caused, the crew will be given the status information of the way that does not respond, so as to make a judgment. Once the 15s time is up, if the self-test does not respond to the way, it still cannot detect what kind of failure is caused. , then the logic is set as a real fire alarm; although this alarm logic design can improve the problem of false alarms (fire detectors alarm when there is no fire), if there is a fire in the engine compartment, due to The fire in the engine compartment quickly burns into a big fire in a very short period of time. It is very important for the crew to take control or fire extinguishing measures in a timely manner. Therefore, when any fire detector of A and B fires, the other does not respond. At this time, the waiting time of 15 seconds may cause the initial small fire in the engine compartment to become a large fire and become uncontrollable, resulting in a delay in the timing of fire extinguishing and a great loss of life and property.

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