What action should be taken if one of the two VHF radios fails while in IFR controlled airspace?

In the event of a VHF radio failure while operating in IFR controlled airspace, promptly notifying Air Traffic Control (ATC) is the most appropriate action to take. This is essential because effective communication is critical for maintaining safety and situational awareness in controlled airspace. By informing ATC of the radio failure, they can provide guidance, adjust your flight plan if necessary, and help ensure that you remain adequately separated from other aircraft.

ATC relies on your ability to communicate effectively to manage air traffic and provide you with instructions for your flight. This communication includes receiving clearances, instructions, and any critical updates regarding the airspace environment. By alerting them to the issue, they can also be on the lookout for you if further complications arise.

While switching to the second VHF radio is a reasonable action, it does not replace the need to inform ATC. If the backup radio fails or if there are other issues related to the aircraft, ATC needs to be aware of the situation to provide appropriate support. Continuing to fly without any further action would not be advisable, as it could lead to misunderstandings and safety risks. Making an emergency landing would only be warranted in more dire situations where the aircraft's safety is at immediate risk, rather