15.20 Fire Protection Systems Flashcards
What are the 2 major types of turbine failures?
Thermodynamic.
Mechanical.
What is a fire zone?
A zone designated by the manufacturer to require fire detection and/or fire extinguishing equipment.
What does a thermodynamic turbine failure cause?
Reduces the proportion of air used to cool down combustion temperature.
A thermodynamic turbine failure can be caused by ice, what effect could this have?
Severe overheating.
What is a mechanical turbine failure?
A fractured or thrown blade.
Due to a mechanical failure, what can cause a burn through of the tail cone?
High flow of fuel through an improperly adjusted fuel nozzel.
What are the 3 fire detectors used?
Overheat.
Rate of temperature rise.
Flame.
Do engines have a common fire detection system?
No, separate for each engine.
What are the 2 most common type of fire detection systems?
Spot detectors.
Continuous loop system.
How does a spot detector system work?
Uses individual sensors to monitor a fire zone.
What does a continuous loop detection system use?
Uses several loop type sensors.
Where are thermal switch systems used?
On older aircraft.
How are thermal switches connected in a circuit?
In parallel with each other.
In series with indicator lights.
How does a thermal switch system work?
Heat sensitive units complete a circuit at a set temp.
What does a thermocouples system depend on?
Depends on rate of temperature rise.
Will a thermocouples system give a warning if an engine slowly overheats?
No
How does a thermocouples system work?
Produces a voltage because of a temperature difference between a hot and reference junction.
What controls the warning lights in a thermocouple system?
Relays.
What are the 2 types of optical fire detectors?
Infrared and ultraviolet.
Where are infrared optical fire detection systems used?
On light turboprop aircraft and helicopters.
What does a pneumatic thermal fire detection system consist of?
A closed helium filled tube
What does the pneumatic fire detection system respond to?
An overall average temp threshold.
And a localised discrete temp increase.
What is the purpose of the integrity pressure switch in a pneumatic fire detection system?
Triggers a fault alarm in case of a leak.
What is the average temp sensing range?
200 to 700 F
93 to 271 C
