11.19 - Integrated Modular Avionics (ATA 42)

Question 1

What is IMA and explain its philosophy?

Answer 1

Integrated Modular Avionics (IMA) means that multiple different system functions are combined into a single piece of equipment, it also includes a design method that allows systems to be divided into separate replaceable modules.

IMA represents how avionic systems are put together and this improves reliability and reduces weight of having multiple systems performing different functions.

Question 2

Give 6 Advantages of IMA

Answer 2

Redundancy, improved reliability of Avionics as black boxes are interconnected to a mainframe meaning if one fails, the system does not fail as it can draw power from another black box

Reduction in weight of avionic systems

Reduces flight crew workload by reducing the number of indicators to be observed during flight as well as reducing instrument panel complexity.

Less electrical power is required to operate the systems

Less space is used as not as much wires, LRUs and indicators are needed as indicators/systems are integrated.

Instrument panels are less complex and less crowded

Question 3

Explain ARINC 429, ARINC 629 and AFDX give their transmission /speeds rates.

Answer 3

These are digital data bus systems and reduce the number of wires needed to transfer data by transferring the data serially (one piece of information after another rather than simultaneously). Digital Data buses use fewer wires which may be twisted together and are usually protected from EMI by a braided sheild.

ARINC 429 can transfer 100 000 bits of information per second

ARINC 629 can transfer 2 000 000 bits of information per second

AFDX (Avionics Full Duplex) can transfer 100 000 000 bits per second

Question 4

What aircraft uses IMA? Name 4 types of aircraft

Answer 4

Airbus A380, A350

Boeing 777, 787

Question 5

Explain “core system” and” network components”

Answer 5

The core system consists of the processing circuitry that is shared and integrated by multiple avionic systems. It processes data from various sensors, LRUs and controls calculating different items such as if stall warning should be activated based on parameters it is receiving or throttle setting for best fuel economy. The core system can hten send out commands or information to actuators or displays.

Network components allow data to be transferred to and from the core systrem. Network components include input and output devices as well as data bus wiring.