Questions and Answers
Briefly describe the components of a thermal switch fire detection system?
Temperature sensitive switches that complete a circuit at a specific temperature and trigger a warning.
Are thermal switches wired in series or parallel with each other?
Parallel.
How are the detector units in a double-loop Fenwal system wired?
In parallel between two complete loops of wire.
In what way is a thermocouple fire warning system different from a thermal switch system?
Signup and view all the answers
Briefly describe the components of a Kidde continuous loop fire detection system.
Signup and view all the answers
Briefly describe the components and operation of a Lindberg fire detection system?
Signup and view all the answers
Describe the process or mechanism by which a photoelectric smoke detector generates a warning of a possible fire.
Signup and view all the answers
How can the operation of a photoelectric smoke detector be tested?
Signup and view all the answers
Name two types of smoke detection systems used in aircraft.
Signup and view all the answers
What are the usual locations where a carbon monoxide detector would be installed?
Signup and view all the answers
How does a carbon monoxide detector indicate the presence of this deadly gas?
Signup and view all the answers
What are the possible effects of kinks and sharp bends in the sensing element(s) of a fire warning system?
Signup and view all the answers
How is a Freon container checked for proper pressure?
Signup and view all the answers
Name the two basic types of fire extinguishing systems.
Signup and view all the answers
Name the extinguishing agent most commonly used in conventional fire extinguishing systems.
Signup and view all the answers
Name the extinguishing agent most commonly used by high-rate discharge fire extinguishing systems.
Signup and view all the answers
How are Freon bottles protected from excessively high temperatures and how can you tell that this has occurred?
Signup and view all the answers
What condition is indicated if the yellow disk is missing in a fire extinguishing system?
Signup and view all the answers
Describe the mechanism by which a Freon bottle is discharged.
Signup and view all the answers
How is the service life of a discharge cartridge calculated?
Signup and view all the answers
Does a thermocouple fire detection system warn the pilot of a general overheat condition?
Signup and view all the answers
Does a thermal switch fire detection warn the pilot of a general overheat condition?
Signup and view all the answers
What type of fire extinguishing agent is best for both cabin fires and engine fires?
Signup and view all the answers
What is a major disadvantage of 'CB' fire extinguishing agent for extinguishing aircraft fires?
Signup and view all the answers
Why is carbon tetrachloride not recommended as a fire extinguishing agent?
Signup and view all the answers
Study Notes
Fire Detection Systems
- Thermal switch systems consist of temperature-sensitive switches that complete circuits upon reaching specific temperatures, triggering warnings.
- Thermal switches are wired in parallel, ensuring that if one switch is activated, others can still function.
- In a double-loop Fenwal fire detection system, detector units are wired in parallel across two complete loops of wire.
- Thermocouple systems are responsive to the rate of temperature change, unlike thermal switch systems, which react to absolute temperature values.
- The Kidde continuous loop fire detection system comprises an Inconel tube containing wires embedded in a ceramic core, where resistance changes with temperature.
Fire Detection Technology
- The Lindberg fire detection system uses a stainless steel tube filled with inert gas. Heat release raises pressure, activating a pressure switch.
- Photoelectric smoke detectors work by using light refraction caused by smoke particles, triggering an electric signal to sound an alarm.
- Testing a photoelectric smoke detector can be done by actuating a test switch.
- Two common smoke detection systems in aircraft are light refraction (photoelectric) and ionization types.
Carbon Monoxide Detection
- Carbon monoxide detectors are typically installed in aircraft cockpits or cabins.
- Detection of carbon monoxide is indicated by a change in color of a tan spot to gray or black on the detector.
Fire Warning Systems
- Kinks and sharp bends in fire warning system sensing elements can cause false fire warnings due to short circuits.
- Freon containers are checked for proper pressure using a chart that correlates gauge readings with ambient temperatures.
Fire Extinguishment Systems
- There are two basic types of fire extinguishing systems: conventional systems and high-rate discharge systems.
- The most common agent in conventional fire extinguishing systems is carbon dioxide (CO2), while high-rate discharge systems typically use Halon (halogenated hydrocarbon agents).
- Freon bottles are equipped with thermal fuses (or blowout disks) that release the agent if temperatures exceed safe limits, indicated by a blown red disk.
- The absence of a yellow disk in a fire extinguishing system signifies that the system has been discharged normally.
Discharge Mechanisms
- Freon bottles are discharged via an electrical signal that activates an explosive squib to rupture a frangible disk.
- The service life of a discharge cartridge is determined from the manufacturing date stamped on it.
Additional Information
- Thermocouple fire detection systems do not warn pilots of general overheat conditions, as they are designed to detect only fires.
- Thermal switch fire detection systems also do not provide warnings for general overheat conditions.
- Halon 1301 is the preferred extinguishing agent for cabin and engine fires.
- A significant drawback of "CB" extinguishing agents is their corrosive nature towards aluminum and magnesium components.
- Carbon tetrachloride is not advisable as a fire extinguishing agent because it generates phosgene, a toxic gas, when exposed to flames.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your knowledge about fire protection systems in airframes with these flashcards. Learn about thermal switches, their wiring configurations, and the components of fire detection systems. A great way to prepare for exams in aviation safety.