Module 5 - digital techniques

What is the basic 6 instruments ? And there functions.

Airspeed indicator - how fast you are travelling in knots

Attitude director indicator - displays attitude (gyro horizon)

Altimeter - displays altitude level

Turn co ordination

Vertical speed - your climb speed

Horizontal situation indicator - what direction you are facing

What are the 4 instruments included on the basic T model?

Airspeed, attitude director indicator, altimeter, horizontal situation indicator

Draw out the basic t model.

Top left - airspeed

Top middle - attitude director indicator

Top right - altimeter

Bottom middle - horizontal situation indicator

What is EIS?

Electronic instrument system

What are the benefits of EIS?

• easier for the pilot, reduces there work load

• Easier maintenance as they are easily swappable

• Redundancy

What are the main displays in Boeing aircraft?

EADI - electronic attitude director indicator

EHSI - electronic horizontal situation indicator

EICAS - engine indicating crew alert system

What are the main displays in Airbus aircraft?

PFD - primary flight display

ND - navigation display

ECAM - centralised aircraft monitoring

How is data mainly handled ?

Usually by data busses, mainly ARINC 429

What is a bit?

Short for a single binary digit either 0 or 1

What is a byte?

Group of bits (8 bits), enough for 1 letter

What is an instruction ?

An instruction is a single command

What is a command?

A command is a set of instructions

What is software?

Programs that tell hardware what to do

What is hardware?

Physical equipment used for input or output

What is RAM?

Random access memory, is temporary storage

What is ROM?

Read only memory, permanent storage.

What is PROM?

Programmable read only memory, is single use only.

What is EPROM?

Erasable PROM that can be reprogrammed via use of UV light

What is EEPROM ?

Electrically erasable PROM that can be reprogrammed via electricity within the computer

What is flash memory ?

Modern even faster EEPROM.

What is firmware?

Firmware is software for the ROM, made specifically for hardware

What is an address?

Address is the location of data within the memory

What is the CPU?

Central processing unit, fetches and executes instructions, the “brains”

What is the ALU?

Arithmetic logic unit - completes the arithmetic and logical instructions

What is the CU ?

CU - controlling unit, controlling flow of instructions

What is an integrated circuit ?

Full circuits printed on silicon wafers

They are installed using dual in line package or dilp where the terminals are standardised

What is an address bus?

An address bus sends memory locations, and is a parallel bus.

What is a data bus?

A data bus sends actual data to and from the cpu, I/o and memory

What is a control bus?

A control bus sends control data/signals e.g. read or write. From cpu to memory or I/o system.

What is a serial bus?

Connects i/o system to external devices, and is serial

What is the basic computer structure ?

Input, processing with alu and cu, memery ram or rom, and then output

What is a reference computer?

A reference computer provides fixed data to other systems e.g. the ire, using gyroscopes and pitot system

What is an informational computer?

Provides data to crew for example the EICAS

What is a Storage computer?

A storage computer is recording and storing data, like fault and errors

What is a Controlling computer?

A controlling computer controls a mechanical or electrical system like the flap/slats unit

What is an interactive computer?

Is a computer that interacts with crew and responds to inputs, for example the fmu.

What is a ESD/ESDS?

An electrostatic sensitive device. A device that is at risk of damage / sensitive to static shock

What factors affect static electricity levels ?

Humidity - low is more static

Temperature

Material

Type of movement

What damage can be caused by static to SSD

When static occurs, high uncontrolled current flows. Can caused cracking or thinning of layers, evaporation of material can occur as well as local overheating

What precautions can be taken against static electricity?

Grounding of yourself, tools, workbench and anything else

Transport in anti static packaging

Handle like new

Anti static bands

Is most static damage visible ?

No, mostly invisible.

Can equipment testing show static electricity damage?

No, BITE and ATE checks can only detect full faults and failures not partial damage.

Who does the most damage to aircraft equipment?

Engineers, by mistake, due to lack of training and awareness.

What voltage can be produced by just walking on carpet?

Up to 15000v

What is known as read write memory?

RAM