Electronic Instrument Systems in Aviation

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What was the primary issue with early aircraft instrument panels?

Instruments were not reliable

Difficulty in reading the instruments

Variation in instrument layout between aircraft (correct)

Lack of instruments

What were the typical instruments found in early aircraft?

Airspeed Indicator, Compass, and Clock

Airspeed Indicator, Attitude Indicator, and Compass

Altimeter, Compass, and Clock

Compass, Clock, and Altimeter (correct)

What was the significance of the Basic T configuration?

It made critical information immediately identifiable in an emergency (correct)

It was a more compact layout

It made instruments more readable

It was only used in military aircraft

What was the primary advantage of the Basic T configuration?

It enabled pilots to fly in the dark or poor weather Signup and view all the answers

When did the Basic T configuration become widely used?

After 1950 Signup and view all the answers

What instruments were typically placed in a row in the Basic T configuration?

Altimeter, Attitude Indicator, and Airspeed Indicator Signup and view all the answers

Why was the compass placed below the row of instruments in the Basic T configuration?

To enable pilots to fly in the dark or poor weather Signup and view all the answers

What was the primary reason for developing standardized instrument layouts?

To enable pilots to fly multiple aircraft types Signup and view all the answers

What is the primary function of electronic flight instruments in an aircraft?

To provide the flight crew with primary aircraft operational information Signup and view all the answers

What is the advantage of using EFIS systems over analogue instrument-based cockpits?

Reduced number of devices to scan and reduced instrument clutter Signup and view all the answers

What is the purpose of symbol generators in an EFIS system?

To drive the displays and provide graphical information Signup and view all the answers

What is the advantage of using multifunction displays in an EFIS system?

Allows for the display of additional information beyond EADI and EHSI Signup and view all the answers

What is the purpose of the EADI and EHSI displays in an EFIS system?

To provide navigation and attitude information Signup and view all the answers

What is the benefit of having interchangeable displays in an EFIS system?

Improved maintenance and reduced downtime Signup and view all the answers

What is the primary source of information for EFIS displays?

Sensors and avionics data buses Signup and view all the answers

What is the purpose of a centre symbol generator in an EFIS system?

To take over primary symbol generator functions in case of failure Signup and view all the answers

What type of information does the ND display in a Boeing 737?

Terrain information and weather radar information Signup and view all the answers

What is the system used by Boeing to provide airframe and engine data?

EICAS Signup and view all the answers

What is displayed on the primary and secondary screens in a Boeing system?

Primary and secondary engine data Signup and view all the answers

What is the system used by Airbus to provide engine, system, and synoptic information?

ECAM Signup and view all the answers

What is displayed on the screens in an Airbus system?

Primary and secondary engine data, visual cautions, warnings, and memos Signup and view all the answers

What is the purpose of the EICAS system in a Boeing aircraft?

To provide airframe and engine data, visual cautions, warnings, and memos Signup and view all the answers

What is the module and topic where more information on the EFIS and EICAS is provided?

Module 5 Topic 15 Signup and view all the answers

What is the name of the instrument panel layout used in a Boeing aircraft?

Boeing instrument panel layout with EFIS and EICAS displays Signup and view all the answers

What is the primary purpose of duplicating data buses in digital systems?

To provide redundancy in case of system failure Signup and view all the answers

What type of converters are used to pass information from analogue systems to digital systems?

ADCs (Analogue-to-Digital Converters) Signup and view all the answers

What is the main function of a Symbol Generator Unit (SGU) in an Electronic Display System?

To receive and process all aircraft sensor inputs Signup and view all the answers

What is a common failure mode in digital systems?

Short circuit between a terminal and earth Signup and view all the answers

What is the purpose of a digital-to-analogue converter (DAC) in a digital system?

To convert digital signals to analogue signals Signup and view all the answers

Why do commercial aircraft typically have at least two symbol generators?

To provide redundancy in case of system failure Signup and view all the answers

What is the term used to describe the separate buses in parallel in a digital system?

Channels A and B Signup and view all the answers

What is the most common failure mode when a connector is not installed correctly?

Signal loss due to poor connector contact Signup and view all the answers

What is the main function of the symbol generator in an electronic instrument display system?

To process information from the data bus and send it to the display Signup and view all the answers

What happens when two channels of the data bus fail?

The other symbol generators can still function Signup and view all the answers

What type of data is sent from the symbol generator to the I/O processors?

Raw data from the data bus Signup and view all the answers

What is the role of the main processor in the display system?

To control all activities to prevent clashes between I/O and display controller Signup and view all the answers

What type of display bus is used to send information from the symbol generator to the display?

Display bus Signup and view all the answers

How many separate channels of a data bus can be used in a display system?

Three Signup and view all the answers

What happens when a symbol generator fails?

The back-up unit takes its place Signup and view all the answers

What are the two types of data that can be written on the screen?

Stroke and raster Signup and view all the answers

Study Notes

Conventions and Development of Electronic Instrument Systems

Early aircraft had only a clock and a compass, which was acceptable for daytime flights in clear weather.
As more instruments became available, they were arranged randomly on the instrument panel, causing problems for pilots flying multiple aircraft.
After 1950, most aircraft cockpits adopted the Basic T configuration, with an Airspeed Indicator, Attitude Indicator, and Altimeter in a row, making essential information easily accessible in emergencies.

Arrangements of Electronic Instrument Systems

Electronic Flight Instrument Systems (EFIS) provide all primary aircraft operational information on display screens, reducing instrument clutter and maintenance needs.
A typical EFIS system consists of four interchangeable displays: two EADI (Electronic Attitude Director Indicator) and two EHSI (Electronic Horizontal Situation Indicator), three symbol generators, two control panels, and two source selection panels.

Cockpit Layout of Electronic Instrument Systems

The Boeing system uses the Engine Indicating and Crew Alert System (EICAS) to display airframe and engine data, and indicate visual cautions, warnings, and memos.
The Airbus system uses the Electronic Centralised Aircraft Monitor System (ECAM) to display engine, system, and synoptic information, and indicate visual cautions, warnings, and memos.
Both systems use primary and secondary screens to display primary and secondary engine data, respectively.

Data Buses and Symbol Generators

Data buses are duplicated for redundancy, with channels A and B carrying the same information to ensure system operation if one bus fails.
Symbol generators receive all aircraft sensor inputs, process and transmit information to electronic displays, and provide analogue, discrete, and digital signal interfaces.
Commercial aircraft typically have at least two symbol generators, with some systems having an additional unit for redundancy.

Basic Operation of Aircraft Display Systems

Symbol generators receive information from the data bus and send it to the display, as selected by the aircrew.
All symbol generators receive the same data from the data bus, allowing back-up units to take over in case of failure.
Display systems use up to three separate channels of a data bus, and can still function if two channels fail.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Learn about the typical arrangements and cockpit layouts of electronic instrument systems in aviation, including their history and development.