What is the international emergency frequency for aviation communication?

The international emergency frequency for aviation communication is 121.5 MHz. This frequency is universally recognized and designated for distress and emergency situations in aviation. It is used for emergency calls by pilots, allowing them to communicate with air traffic control and other aircraft in the vicinity if they are in distress or experiencing difficulties.

121.5 MHz is monitored by air traffic control stations and can be accessed by all aircraft equipped for VHF communication. Additionally, it is utilized by various emergency locator beacons which transmit on this frequency in case of an accident, thus aiding search and rescue operations.

The other frequencies listed, while they may serve specific communication purposes, are not designated for emergency use. For instance, 123.45 MHz is commonly used as a non-towered airport common traffic advisory frequency, while 119.0 MHz is typically assigned to certain air traffic control services, and 130.0 MHz may be used for specific operational communications but does not hold the international emergency designation.