7/27/2019 System description.docx

1/2

1. There had 2 types of fire engine fire detection systema. Spot-detection type :

i. have individuals switches used to detact fireii. usually placed where fire likely to occur

b. continuous- loop type :i. utilize only one switch in form of long tube

ii. a small diameter tube run completely around engine nacelle or tail coneiii. allowing more complete coverage of detection.

2. Thermal switch fire detection system is a spot-type detection system. Each of the sensorsconsist of bimetallic thermoswitch that are closed and complete the circuit when heated

to a predetemined temperature.

3. Thermal switch fire detection system is a spot-type detection system, and for thatreason, it utilize a number of thermal switches in that system.

4. Continous-loop type system5. In a thermocouple fire warning system, the detectors trigger by the rate of temperature

rise rather than a preset temperature, it will light the warning light if the temperature of

serounding air rises too rapidly. If the termocuope heat slowly, then the warning light

will not trigger.

6. Direct current7. False fire warning is likely to occur because of intermitten short circuit in detection

system warning.

8. A fire extinguishing system are designed to dilute oxygen levels to a point that does notsupport combustion or to reduce the tempereture below the ignition point.

9. Both Kiddie and Fenwall continuous loop fire protection system function an overheatsensing element that varies in length

a. Fenwall = when fire or overheat condition occur, the core resistance drops andcurrent flows between the center conductor and ground, energizing the alarm

system.

b. Kiddie = when fire or overheat occurs, the resistance of thermistor meterial drop,allowing current to flow between the two wires to activate an alarm.

10. There have three element that must be present in order to get fire, combustible fuel,oxygen, and heat.

11.A group of fire extinguisher agents that no longer manufactured is halogenatedhydrocarbon.

12. Fire extinguishing agents is distributed electrically firing catridge units within the

extinguisher discharge heads. The firing unit are controlled by switches or fire control

handles in the flight crew compartment, in some aircraft control may also be automatic in

the event of landing.

13. The discharge catridges used with HRD containers are life-limited and the service life is

calculated from the manufacturers date stamped on the catridge. The discharge catridge is

ignited electrically and it is used to fires a projectile into the frangible disk.

7/27/2019 System description.docx

2/2

14. HRD system typically utilize haligenated hydrocarbins typically consist of a container to

hold the extinguishing agent, at least one bonnet assembly and series of high-pressure

feedline.

15. Red discis set to rupture and discharge the carbon dioxide overboard if the cylinder

pressure becomes excessively high (about 2650psi)Yellow discwill ruptures whenever a bank of bottles has been emptied by normal

discharge.

16. the extinguishing agent is released within one to two seconds by an electrically actuated

explosive that ruptures a frangible disk. Once broken, the disk fragments collect in a strainer

while the extinguishing agent is directed to the engine nacelle.

17. It is used to indicate the pressure of the bottle, and an electrical pressure switch is

mounted on each bottle to activate a bottle discharge light on the instrument panel when

the pressure on the agent bottle is below limits.