B1 Avionics crossover Flashcards
Which one of the following in NOT a factor affecting the resistance of a wire conductor?
A. Cross sectional area
B. Length
C. Insulation type
C. Insulation type
Which of the following is the best material to surround an item with to isolate it from the effects of a strong magnetic field?
A. Aluminium
B. Mu-Metal
C. Copper
B. Mu-Metal
When preparing an Electrostatic Sensitive Device (ESD) for transport, you should…
A. Place equipment in Styrofoam chips to minimize vibration
B. Ensure packaging is properly sealed using cellulose tape
C. Attach warning labels on packaging to inform personnel of the nature of the equipment
C. Attach warning labels on packaging to inform personnel of the nature of the equipment
A typical digital integrated circuit application would be as a…
A. Counter
B. Voltage regulator
C. Amplifier
A. Counter
A PCB is protected from dust chemicals and temp extremes by…
A. The application of a conformal coating
B. Applying varnish to the component side
C. Dipping entire assy into molten wax
A. The application of a conformal coating
The role of ROM is to…
A. Store data, intermediate results and program instructions
B. Temporarily store data and programs
C. Provide storage for any data that requires permanent storage
C. Provide storage for any data that requires permanent storage
The important difference between static and dynamic RAM is that dynamic memory…
A. Does not require periodic replacement
B. Requires periodic replacement
C. Requires periodic refreshing
C. Requires periodic refreshing
Which of the following devices provide a linear output from an angular displacement input?
A. Liner Variable Differential Transformer (LVDT)
B. Inductive Proximity Transducer
C. Rotational Variable Differential Transformer (RVDT)
C. Rotational Variable Differential Transformer (RVDT)
With reference to A/C displays, select the most correct statement.
A. Electronic instrument systems (EIS) have one control and display unit (CDU) per display for each crew member
B. The PFD follows the convention of “T” arrangement of instruments
C. LED’s are much more reliable that conventional filament lamps.
C. LED’s are much more reliable that conventional filament lamps.
The purpose of the PFD is to…
A. Interact with a system to give it commands
B. Monitor the engine and flight controls
C. Display the data that the pilot need to easily access to fly the aircraft
C. Display the data that the pilot need to easily access to fly the aircraft
Select the most correct answer.
The MIL-STD-1553 bus…
A. Uses a bus controller, a backup bus controller, and a bus monitor
B. Is limited to one transmitter and multiple receivers
C. Is an asynchronous serial communication method
A. Uses a bus controller, a backup bus controller, and a bus monitor
With reference to data buses, select the most correct statement
A. The use of a data bus add weight to the A/C
B. Cryptographic info should not be allowed to be passed around a central data bus with other info.
C. Nav data - INS, GPS, VOR/ILS etc have dedicated buses
B. Cryptographic info should not be allowed to be passed around a central data bus with other info.
At the heart of a fly-by-wire system are…
A. Electrical wire connections driving motors
B. Computers that convert the pilot’s commands into electrical signals
C. Servos and actuators that drive the control surfaces
B. Computers that convert the pilot’s commands into electrical signals
The engine indication and crew alert system (EICAS) provides…
A. All engine instrumentation and crew annunciations in an integrated format
B. Management functions for A/C Aux systems and indicates their status
C. Computation of flight control inputs and provides outputs to flight control surfaces
A. All engine instrumentation and crew annunciations in an integrated format
Which aeronautical software classification level is deemed as having ‘a minor failure condition for the A/C’?
A. Level C
B. Level D
C. Level B
B. Level D
The definition of a electro-magnetic interference (EMI) can be re-phrased as…
A. Any electro-magnetic energy that degrades electronic equipment performance
B. A large scale spark discharge that can damage A/C radomes and skin
C. The effect on the capability of the A/C to receive radio transmissions
A. Any electro-magnetic energy that degrades electronic equipment performance
WRT lightning strikes,
A/C composite panels often consist of a ply or layer of conductive material primarily to…
A. Better indicate the entry and exit points after a lightning strike
B. Improve electrical bonding between structures
C. To help dissipate the high currents resulting from a lightning strike
C. To help dissipate the high currents resulting from a lightning strike
The purpose of a reverse current cut out (RCCO) is to disconnect the DC bus in certain conditions to prevent the…
A. Gen voltage exceeding the battery voltage
B. Battery discharging through the Gen
C. Gen overcharging the battery
B. Battery discharging through the Gen
Fuses in A/C are classified as…
A. Cartridge, slow blow and clip types
B. Cartridge, plug in and heavy duty types
C. Cartridge, plug in and clip types
C. Cartridge, plug in and clip types
If the output of a Gen is low, the voltage regulator will excite the…
A. Field with higher average voltage
B. Armature with a higher average voltage
C. Field with the lower average voltage
A. Field with higher average voltage
WRT lighting safety precautions, select the most correct statement
A. Landing lights do not require ram-air cooling
B. LED lenses require cleaning after handling
C. Precautions must be in place for testing strobe lights.
C. Precautions must be in place for testing strobe lights.
While testing/operating high wattage lamps…
A. Minimize light pollution to the surrounding area
B. Wear dark sunglasses to prevent eye damage
C. Ensure skin does not contact the lens as serious burns could result.
C. Ensure skin does not contact the lens as serious burns could result.
Emergency lighting…
A. Provides illumination of the cockpit and various sections of the cabin, exits, escape hatches, chutes etc
B. Operates from the essential DC bus
Illuminates all internal areas of the A/C
C. Illuminates all internal areas of the A/C
A. Provides illumination of the cockpit and various sections of the cabin, exits, escape hatches, chutes etc
The applied DC voltage when carrying out an insulation test on A/C wiring should be…
A. At least twice the working voltage
B. Same as the working voltage
C. 28V
A. At least twice the working voltage
In a live circuit, if the probes of a digital multi-meter (DMM) were in series with a component, the user would be attempting to measure…
A. Total circuit current
B. Voltage through a component
C. Current through a component
C. Current through a component
For shock hazard protection, the acceptable resistance carrying out a grounding point bonding test must not be greater than…
A. 1.0 ohm
B. 0.1 ohm
C 0.01 ohm
B. 0.1 ohm
You have inspected an area that you have worked in. A flexible type coaxial cable travels through a lightening hole, and then turns 90 degrees. The cable measures 6mm across its diameter.
Which of the following is the min bend radius for the cable?
A. 90mm
B. 36mm
C. 9mm
B. 36mm
SWAMP areas need particular attention during inspections. An example of a SWAMP area would be…
A. In the flap well area
B. Around the galley area under the sink
C. The area around the hydraulics reservoirs
A. In the flap well area
The dry operating weight of an A/C normally includes…
A. Unusable fuel and oil
B. Role equipment
C. Drainable fuel
A. Unusable fuel and oil
CoG is defined as the point…
A. At which the A/C would balance if suspended
B. At which a wings lift may be assumed to be concentrated
C. From which all weight and balance arm measurements are taken
A. At which the A/C would balance if suspended
Name one of the fundamental laws that static electricity as well as magnets deals with.
Like charges repel each other and unlike charges attract each other
Although most objects become charged with static electricity by means of friction, a charged substance can also influence objects near it by…
Contact or induction
Name the 3 Golden Rules of ESD prevention
- Treat all electronic components and assemblies as statically sensitive
- Handle all sensitive items at statically safe work stations
- Transport and store all sensitive items in statis shielded, non-charge generating packaging.
Describe electron flow.
Movement of negatively charged particles that flow from the negative terminal to the positive terminal.
A North seeking pole has what charge?
Negative charge (South pole)
Opposites attract
Describe the lines of flux
Lines of flux emanate from North poles and re enter at south poles.
What is rententivity
The ability of a magnet to hold its magnetism which varies with the type of metal
Linear (or analogue) integrated circuits produce, amplify or respond to infinitely variable voltages.
Typical applications include…
Amplifiers Voltage regulators Analogue switches Timers Oscillators
Digital (or logic) integrated circuits produce or respond to signals having only two voltage levels. They contain components which are either in a switched on or off condition.
Typical applications include…
Counters Logic gates Microprocessors Memory J-K flip-flops Microcomputers
What’s the difference between a digital and analogue integrated circuit?
Analogue has infinitely variable voltages where digital only has two. ie on or off, or, 1 or 0.
Describe the construction of a single sided PCB
One side of the substrate is coated with a thin layer of metal (typically copper)
Name the 4 characteristics of a CPU
- Is considered the ‘brain’ of the computer.
- Performs all types of data processing
- Stores data, intermediate results and instructions
- Controls the operation of all parts of the computer.
What is the definition of software?
A set of instructions or programs that instructs a system how to preform a task. For example, an operating system.
What is a transducer?
A device that converts energy from one form to another.
Name 2 types of position sensors.
- Linear
2. Rotational
What is the purpose of the FMS?
To provide a visual display of the combination of crew requests and sensor data. It will reduce the pilots workload by eliminating the need to refer to maps, charts and manuals.
Describe ARINC-429
Is a single source, multiple receiver data bus constructed on a unidirectional flow of data.
WRT 1553 data bus, describe the term ‘command/response’
The communication protocol that distinguishes this data bus from others. Basically it is ‘speak only when spoken to’ communication that is solely the responsibility of the designated bus controller.
What is the purpose of ACARS?
It is a digit data link system
providing means by which the ground stations can exchange data with an A/C without human intervention.
Name 4 FBW key functions.
- Computer control reduces the burden in the pilot and makes it possible to introduce automatic control.
- Significant reduction in A/C weight which in turn reduces fuel consumption and helps reduce undesirable CO² emissions
- Computer control can also help ensure an A/C is flown more precisely and always within its flight protection envelope
- FWB technology has made it possible for A/C manufacturers to develop families of very similar A/C with comparable flight deck designs and handling characteristics
What is the RNZAF’s policy on ‘Aeronautical Software Management’?
The configuration of aeronautical software, loadable software, firmware and data is to be controlled in the same manner as aeronautical hardware. ie any changes need to be recorded in CMMS
Describe the 5 levels of software classification
Level A. A catastrophic failure condition for the A/C
Level B. A hazardous/severe - major condition for the A/C
Level C. A major failure condition for the A/C
Level D. A minor failure condition for the A/C
Level E. No effect on A/C operational capability or aircrew workload
What is the definition of E³?
impact of the total EME upon the operational capability of an A/C
Electromagnetic Environmental Effects
What is the definition of Electromagnetic Interference (EMI)?
Any electromagnetic energy which interrupts, obstructs or otherwise degrades or limits the effective performance of electronic equipment.
Name the three elements needed for EMI to exist.
Source, Victim and coupling path.
WRT lightning strikes, where would you typically find the majority of damage?
A. At the point of entry
B. At the point of exit
C. Around lightning diverter strips
B. At the point of exit
WRT A/C wiring, what are the 2 categories that A/C wiring are divided into? And explain why they are separated?
Hostile and passive/sensitive
Sensitive circuits are separated from hostile circuits as a form of protection against EMI.
What is the definition of an inverter and name two common types.
Inverters are devices that allow generation of AC power when only a DC supply is available.
Rotary and static.
Name the 2 ways in which AC power protection is applied.
- protect the A/C and wiring:
isolating the bus by tripping the Gen CB - protect the Gen:
by de-energising the Gen control relay
Describe multiple bus switching
ensure all essential buses are powered in the event of a Gen failure
operates by connecting the bus bar to an alternate Gen should its primary Gen fail
Describe the purpose of interlock circuitry
To ensure no arcing occurs at the high energy pins in the event of the plug being removed with power on.
What is the purpose of wing inspection lights?
Illuminates surfaces (leading edges) prone to icing.
How are landing lights cooled? And what safety precaution should be observed when operating them on the ground?
Rely on ram air.
Operating times must be kept within stated limits to prevent the filament from burning out.
Describe voltage and current measurements in a circuit.
DC & AC voltages measured across the component (in parallel)
DC & AC current measured in line with the component (in series)
What tests should be carried out on an item prior to it being put back in service?
Continuity
Insulation resistance
Contact orientation
When preforming Dye Pen inspection…
A. The defect need not be open to the surface
B. The penetrant solution only works on components made of porous material
C. An ultraviolet light source must be used.
C. An ultraviolet light source must be used.
The active thermography process for the detection of composite material defects uses…
A. An infrared light source
B. A red laser light source
C. An ultraviolet light source
A. An infrared light source
Describe the construction of a multi layer PCB
Consist of 3 or more double layered PCB’s that are secured together with specialized glue and sandwiched between pieces of insulation to prevent overheating.
WRT computers, what are the 3 main buses?
- Data bus
- Address bus
- Control bus
Name the components of a simple computer system
CPU ROM RAM input/output device Linked together using local bus system (3)
WRT Items with magnetic shielding, the lines of flux tend to…
Take the easier path, or the path of greater permeability
What is inductance?
The measure of an inductors ability to store energy for a given amount of current flow.
What is the difference between an open and closed loop servomechanism?
Open loop the operator monitors the output and adjusts the input to suit.
Closed loop the operator sets a control to a specified point and the servomechanism automatically moves the load to the desired position.
Search light vs flaps.
What are the 4 main elements that make up an FMS
- Flight management computer
- Display system
- Database storage unit
- Control display unit with keypad
What does a VNAV system monitor?
Correct speed and altitude
The basic IRS consists of what 4 items?
- Gyroscopes
- Linear accelerometers
- A nav computer
- A clock
What is the definition of the electromagnetic environment?
The operational environments the A/C will encounter.
Not the source of the EM energy
What 2 parameters is EME measured by?
- Frequency
2. Volts per meter (field strength)
Name 2 types of EMI sources and give examples of each.
- Natural Phenomena (lightning, ESD, solar radiation, precipitation static)
- Man-made effects (radio frequency interference (RFI), EMI, RADHAZ, EMP)
Name the 2 ways that EM energy can travel from source to victim.
- Conducted (coupled directly from the source to victim via wiring or metallic structure)
- Radiated (propagates through free space from source to victim eg an antenna)
Explain flood lighting
- lamps or fluorescent tubes positioned to illuminate an entire area/panel. Can be switched to either red (night) or white (day) in colour.
Explain electroluminescent panel
- similar principle as trans-illuminated panels
- instead of incandescent bulbs, 115VAC is applied to a phosphorous track running behind the panel
- the phosphorous powder glows and lighting is diffused through the etched or engraved writing.
- used to Illuminate panel writing, and in strip lighting (emergency lighting)
Explain trans illuminated (edge light) panel
- Used to illuminate the writing on system control panels
- Comprised of several small LED or incandescent bulbs screwed into the back of the panel
- illumination is diffused through the etched or engraved writing on the panel
Explain pillar/post lighting
Single bulb, illuminating individual instruments
WRT Dye pen inspection, how will pits of porosity appear?
As areas of scattered dots of dye
Explain the passage of electricity through…
Solid
Liquid
Gas
Vacuum
Solid - through loosely held outer electrons of the atoms
Liquid - due to the ionisation of certain molecules
Gas - due to the movement of the ionised gas molecules
Vacuum - due to the movement of electrons
Describe the tribo-electric series
The further apart two items are in the series, the greater the voltage.
Name the two types of infra-red thermography used and explain their differences.
- Passive - IR camera used to inspect an A/C after flying operations to detect possible defects due to differing cooling rates.
- Active - introduce heat to the area and monitors the cooling rate through the material. A differing cooling rate may indicate a possible defect.
WRT magnetic particle inspection, what is the difference between direct and indirect magnetism?
Direct - electric current is passed through the test object and a magnetic field is formed.
Indirect - no electric current is passed through the test object, but a magnetic field is applied from an outside source.
WRT ultrasonic testing, what is the purpose of the viscous material, liquid or paste?
ensure strong signal transfer
Name two methods of ultrasonic inspection
Immersion testing
Contact testing
List the fluids that should not be considered as part of the empty weight of an A/C
- Hydraulic fluid
- Potable water
- Engine oil
- Lavatory pre-charge water
- Water for injection into engines
- Unusable fuel
Potable water
Lavatory pre-charge water
Water for injection into engines
The resistance of a wire depends on what 3 factors?
- The material from which it is made
- Length
- Cross sectional area.
Three colours of an anti collision light
- White
- Red
- Infra-red
Name the requirements for external A/C lighting
- Indicate the A/C’s position
- Forward illumination
- Illumination of important areas for de-icing
- Emergency exit lighting
Name the advantages of fluorescent over incandescent lighting
- nearest approach to a daylight effect.
- Low brightness or glare
- uniform illumination over a large area
- Uses ⅓ the amount of energy
Purpose of a Gen control unit (GCU)
Monitors the operating condition ensures that it preforms within parameters
Two most common types of A/C batteries used in the RNZAF
- Lead acid
2. NiCad
Disadvantage of DC Gen over AC gen
DC Gen’s utilise brushes therefore
more friction,
more arching
less current able to be produced.
Difference between inverters and TRU’s
Inverters convert DC to AC
TRU’s convert AC to DC
Name the secondary sources of electrical power on an A/C
- Inverters
- Transformer rectifier units (TRU’s)
- Batteries
Name the primary sources of electrical power on an A/C
- Engine driven generators
2. APU’s equipped with generators.
Technicians E³ responsibilities
- Be aware of E³
- Use correct trade practices - bonding, shielding, separation
- When carrying out maintenance activities ensure bonding requirements are not compromised
- If you are unsure of the serviceability state or it may not be protected against E³, raise the issue with your superior
Name 3 basic ultrasonic inspection techniques
- Pulse echo
- Trough transmission
- Resonance
WRT voltage checks, explain the lead connections
- Check correct configuration
- Connect to the ground first and disconnect the ground last.
- Use high tension probe for measuring high voltages
- Ensure TME input limits are not exceeded
Pre resistance and current measurement checks
- Ensure power supplies are ‘OFF’
2. Ensure capacitive circuits are safely discharged
Safety precautions associated with TME
- Handle with care
- Adhere to the operating/ maintenance manuals
- Ensure TME inputs are not exceeded
Safety precautions when working with Live Voltages
- Safety person
- Remove metallic personal objects
- Ensure live power and signal cut off controls are with in arms reach
- Keep live test leads under control at all times
Internal lighting is used for
Cockpit instrument and control panels
Passenger cabin and passenger information signs
Indication and warning of system conditions
Name the 4 EMC design techniques used for controlling EMI coupling between sources and victims
- Shielding
- Grounding and bonding
- Filtering
- Wiring and separation
WRT radio transmission precautions,
A hazard exists when operating radio equipment because…
- might cause burns or shock
- The charging of metal items in close proximity to the aerial may occur
- The sparking of one charged area to another
- Premature ignition of EED’s
What are the 2 main areas of the body that are sensitive to microwave/RF radiation?
Eyes
Testis
What does HERO, HERF & HERP stand for?
Hazards of electromagnetic radiation to ordnance
Hazards of electromagnetic radiation to fuel
Hazards of electromagnetic radiation to personnel
Name the symptoms of lightning strikes to A/C
Damage to:
radomes/ A/C skin
electrical systems
lights and probes
Name the effects of lightning on A/C
Burning
Eroding
Blasting
Structural deformation
Name 4 main areas (or equipment groups) in respect to E³ victims in the man-made environment.
- Comms, electronic
- Amplifiers
- Industrial
- RADHAZ
Name 6 examples of radiated coupling paths.
- Wire to field
- Wire to wire
- Wire to box
- Wire to ground
- Antenna to Antenna
- Box to box
Describe the reasoning for filters in conducted coupling paths.
The item has failed E³ testing. Said item is either acting as a source or has tested as being susceptible to EMI - a victim.
What does ACARS stand for
aircraft communication addressing and reporting system
Whats the difference between gyroscopes and accelerometers
Gyroscopes- sense directional deviation
Accelerometers- sense speed deviations
How does bonding help in lightning strikes
Provides low impedance paths for lightning current
How do diverted strips help in lightening strikes
If Ac has non metallic skins the lightening flash may puncture the skin and attach to a conductor within
With regards to LRU Testing, what do you need to ensure
Rf bonding between Structure and LRU- 2.5 m ohm
What’s a precaution when using wet lead acid batteries
If the charging current is too high, the gassing rate of hydrogen and oxygen can be a hazard
What is thermal runaway
High battery temperature and overcharging can lead to a chemical fire/ explosion
Ac power circuit protection
Over voltage
Under voltage
Under/over frequency
Differential feeder faults
What is a continuity test
Ensure there is continuity from end to end of every wire
Results: low ohms. 0.5ohms
