What is indicated by the illuminated SEL annunciation on the RMPs?

What is indicated by the illuminated SEL annunciation on the RMPs?

• A. That a radio is being controlled by an RMP that is normally not assigned to the radio.
• B. The SEL annunciation indicates radio is overheated.
• C. That the radio is currently transmitting.
• D. That the RMP is in standby.

Answer: (A)

The name of the game here is who currently has control of a radio. On the A320, two Radio Management Panels can control the radios, and each radio has a normally assigned RMP. When control is taken by the other RMP, the SEL annunciation lights up. That illumination tells you a radio is being controlled by an RMP that isn’t normally assigned to that radio, i.e., a cross‑control situation. It’s a heads‑up that the radio you’re looking at on this panel is actually being managed from the opposite side, so you know which RMP is actively selecting or tuning the radio right now. This light isn’t about overheating, transmitting, or standby status—those would be indicated by other indicators or cues.

The name of the game here is who currently has control of a radio. On the A320, two Radio Management Panels can control the radios, and each radio has a normally assigned RMP. When control is taken by the other RMP, the SEL annunciation lights up. That illumination tells you a radio is being controlled by an RMP that isn’t normally assigned to that radio, i.e., a cross‑control situation. It’s a heads‑up that the radio you’re looking at on this panel is actually being managed from the opposite side, so you know which RMP is actively selecting or tuning the radio right now. This light isn’t about overheating, transmitting, or standby status—those would be indicated by other indicators or cues.