Aircraft Communications Addressing and Reporting System (ACARS)

Question 1

ACARS is found under ATA code:

Answer 1

23-20

Question 2

ACARS is used to:

Answer 2

Send short digital messages automatically
Can be used to send aircraft condition and phase reports to dispatchers

Question 3

Phase of flight reports are commonly known as:

Answer 3

OOOI (pronounced OOHWEE) which stands for Out of gate, Off ground, On ground, and In gate.

Question 4

Like satellite communication systems, the ACARS requires a:

Answer 4

subscription to a service provider.

Question 5

On the aircraft, ACARS is connected to what systems?

Answer 5

VHF communications system and an
HF or a satellite communication system.

Question 6

What is the VHF frequency for ACARS in the United States?

Answer 6

131.550 MHz

(For ACARS to thrive, tune to 131.55)

Question 7

What band is used for ACARS on international flights?

Answer 7

HF

Question 8

The ACARS management unit connects to multiple:

Answer 8

communication systems and sends or receives messages automatically.

Question 9

All ACARs transmissions in the United States are all on one frequency, transmitted messages must be:

Answer 9

as short as possible.

Question 10

To achieve a short message:

Answer 10

a special code block using 220 characters is transmitted in digital format.

Question 11

If there is a longer message:

Answer 11

more than one block will be transmitted.

Question 12

ACARS operates in two modes:

Answer 12

the Demand Mode and the Polled Mode.

Question 13

The Demand Mode allows:

Answer 13

the flight crew or airborne equipment to initiate communications.

Demand Mode: 🗣️➡️

Polled Mode: 📞⬅️

Question 14

The Ground Station sends a reply message. If an error or no reply is received:

Answer 14

the MU continues to transmit the message at the next opportunity.

Question 15

In the Polled Mode:

Answer 15

the system operates only when interrogated by the ground facility.

Demand Mode:🗣️ ➡️

Polled Mode: 📞 ⬅️

Question 16

The Ground Facility regularly:

Answer 16

uplinks questions to the aircraft equipment and the MU responds with a transmitted message.

Question 17

What does the MU do?

Answer 17

organizes and formats flight data prior to transmission.

Question 18

Flight information is transmitted to the ground facility under what circumstances?

Answer 18

Upon request

Question 19

Information for ACARS is collected from:

Answer 19

several aircraft systems including the
FMS, the Aircraft Integrated Data System (AIDS), and the Central Maintenance
Computer Systems (CMCS).

Question 20

The ACARS control is managed through the:

Answer 20

Control Display Unit (Boeing) or the
MCDU (AirBus) located on the flight deck.

Question 21

Various EICAS maintenance pages and CMC fault reports can be sent to:

Answer 21

ground facilities using ACARS.

Question 22

To downlink a CMC fault report or EICAS maintenance page, the crew would:

Answer 22

access the desired fault on the CDU, and then send the report to the ground facility.

Question 23

Some of the newest aircraft will:

Answer 23

automatically downlink maintenance data

Question 24

A BITE circuit within the MU monitors:

Answer 24

the ACARS UM and other related systems.

Question 25

For the link test to work, the aircraft must be:

Answer 25

within range of an ACARS ground station. Keep in mind VHF range is very limited on the ground.