Which statement is true regarding communication and navigation frequencies?

The statement regarding contacting Heritage Creek UNICOM on 122.9 is correct because UNICOM frequencies are often assigned in the range of 122.8 to 123.0 MHz, and 122.9 is commonly used as an airport advisory frequency. UNICOM is a non-governmental communication frequency used for air-to-ground communication at airports, allowing pilots to coordinate their movements and notify others in the vicinity of their intentions.

This reflects the standard use of accepted frequencies within the aviation community, where local airports often use specific UNICOM frequencies to facilitate communications among pilots and ground services.

Other statements do not accurately represent the communication and navigation frequency system. For instance, ATC (Air Traffic Control) frequencies typically vary and are not limited to emergency frequencies, such as 121.5, which is designated solely for distress and emergency communications. Additionally, UNICOM is not fixed at 123.45 for all airports; different airports may have different UNICOM frequencies. Lastly, not all frequencies above 300 MHz are limited to military use; there are various civilian bands that operate in this range as well.