Instruments 2 Flashcards
To what component in a hydraulic pressure indicating system would a pressure transmitter be connected?
The accumulator
Where in a hydraulic pressure indicating system would a pressure switch be located?
Downstream of the hydraulic pump
What is the purpose of a hydraulic pressure indicating system?
- To ensure each system is working properly
- To warn of any problems
What is the purpose of a hydraulic system low pressure warning light?
To give an indication if unsafe hydraulic pressure
What pressure detection/sensing devices may be used in a hydraulic pressure indicating system?
- Bourdon tubes
- Diaphragms
What component, within a hydraulic pressure transmitter, connects the detection device to the synchro transmitter rotor?
A sector gear
List aircraft systems that may utilised hydraulic power for their operation?
- Landing gear
- Brakes
- Flught controls
- Ground steering
- Flaps
- Doors
- Canopies
What are the key components of a hydraulic system?
- Reservoir
- Accumulator
- Hydraulic pump
- Pressure relief valve
- Low pressure sensor
- Hydraulic system temperature sensor / bulb
- Hydraulic system pressure sensor / transmitter
What unit of measure is normally displayed on the dial of a hydraulic pressure indicator?
Pounds per square inch (PSI)
What type of pressure detector / sensor is typically employed in a low pressure warning system?
A diaphragm
What colour is used for a low pressure warning light?
Amber
What components make up a hydraulic temperature indication system?
- Temperature sensor
- Indicator
- Interconnecting wiring
In reference to a hydraulic system temperature indicating system - where is the temperature sensor normally fitted?
Just prior to the oil returning to the reservoir
Why is it important to monitor the temperature of hydraulic oil?
Above certain temperatures, the viscosity of the hydraulic oil changes - this then downgrades the performance of it
Type of temperature sensor used in a hydraulic oil temperature indicating system?
A bulb sensor
What type of quantity indication do the below use:
- Hydraulic oil reservoir
- Engine oil
Sight gauge
DC synchro system
The wiper arm in an engine oil quantity transmitter is connected to what component in the oil tank?
A float and actuator
3 types of fuel flow indicating systems?
- Rotating vane
- Impeller
- Fuel mass flow
What output is provided by a fuel flow transmitter?
Electrical output signal proportional to the flow rate
What type of fuel flow indicating system is used to counter the problem of fuel density varition?
A mass fuel flow indicating system
In a rotating vane type fuel flow transmitter, what opposes the movement of the metering vane?
A calibrated spring
In a rotating vane type fuel flow transmitter, what component (driven by the metering vane) provides a DC voltage proportional to the fuel flow?
A wiper across the potentiometer
In a rotating vane type fuel flow transmitter - what provides a path for the fuel low in case the vane becomes jammed closed?
Bypass valve
In an impeller type fuel flow system - what component converts the transmitters pulsing signal into one that is used to drive the indicator pointer?
The amplifier / signal conditioner
What ‘relationship’ is used by a mass flow fuel indicating system?
Fuel mass and viscosity
What components make up an integrated fuel flowmeter system transmitter?
- Housing
- Motor driven impeller assembly
- Flow metering chamber
- Externally mounted magnetic pick-off assembly
How are the outer drum and impeller assembly in an integrated fuel flowmeter transmitter coupled to each other?
By calibrated spring
What are the 2 components in the integrated fuel flowmeter transmitter, are the magnets fitted to?
- Outer drum
- Impeller
Under which condition are the integrated fuel flowmeter transmitter magnets in alignment?
Under zero fuel flow conditions
3 functions performed by the integrated fuel flowmeter system computer?
- Proved power for various cct of the system
- Detects the number of pulses produced by the transmitter
- Computes and integrates the fuel flow rate and fuel consumed for the display indicator
What 2 pieces of information are displayed on an integrated fuel flowmeter indicator?
- Fuel flow
- Fuel used / remaining
What does the computer in a fuel remaining / fuel used indicating system calculate?
Fuel consumed over a period of time from the flow rate during the period
What is provided on a fuel remaining / fuel used indicator to reset the counters to zero?
Mechanical reset button
What component within an integrated fuel flowmeter indicator provides feedback to the computer if the pointer position does not represent the fuel flow from the transmitter?
Timebase section
What type of transmitter is used in a volumetric fuel quantity indicating system?
Float arm type transmitter
What type of transmitter is used in a mass type fuel quantity indicating system?
Capacitance fuel probes
What 3 types of meter movements may be used in a volumetric fuel quantity indicating system?
- Milliammeter
- Ratiometer
- Desynn and autosynn
What type of cct is used to indicate fuel contents in a capacitance fuel quantity indicating system?
A balanced bridge cct