If the ACARS system becomes inoperative enroute, what is the role of SELCAL?

If the ACARS system becomes inoperative enroute, what is the role of SELCAL?

• A. If SELCAL is working, ARINC frequency monitoring is not required
• B. SELCAL is used to replace ARINC entirely
• C. SELCAL has no effect on ARINC monitoring
• D. SELCAL tasks do not apply when ACARS is down

Answer: (A)

When ACARS is inoperative, the aircraft can still be reached via selective calling, which is SELCAL. SELCAL is designed to alert the crew to an incoming call on the voice channel without having to listen to all frequencies continuously. If SELCAL is functioning, you don’t need to rely on ARINC frequency monitoring to know when someone is trying to reach the airplane, because SELCAL will notify the crew of a call, allowing them to respond on the voice channel. SELCAL does not replace ARINC for data messages; it only provides an alert mechanism for selective voice calls. Therefore, ARINC monitoring isn’t required for ACARS communication when ACARS is down, but SELCAL alerts remain relevant. The other options misstate SELCAL’s role or its applicability when ACARS is unavailable.

When ACARS is inoperative, the aircraft can still be reached via selective calling, which is SELCAL. SELCAL is designed to alert the crew to an incoming call on the voice channel without having to listen to all frequencies continuously. If SELCAL is functioning, you don’t need to rely on ARINC frequency monitoring to know when someone is trying to reach the airplane, because SELCAL will notify the crew of a call, allowing them to respond on the voice channel.

SELCAL does not replace ARINC for data messages; it only provides an alert mechanism for selective voice calls. Therefore, ARINC monitoring isn’t required for ACARS communication when ACARS is down, but SELCAL alerts remain relevant. The other options misstate SELCAL’s role or its applicability when ACARS is unavailable.