How should DSC relays of distress alerts be handled if the original DSC call is not acknowledged?

The handling of DSC relays for distress alerts is a critical component of maritime communication procedures. In the context of the given question, the correct approach is to use Inmarsat-C TELEX for conveying follow-on distress traffic if the original distress alert sent via Digital Selective Calling (DSC) is not acknowledged.

Using Inmarsat-C TELEX allows for a reliable communication pathway to ensure that the distress message is transmitted effectively, especially given the satellite system's robustness and ability to relay messages without the need for immediate vessel-to-vessel communication. This is particularly important in situations where the distress alert may not be acknowledged due to radio propagation issues, technical problems, or the complete unavailability of other vessels within radio range.

In scenarios where no acknowledgment occurs, relying solely on other forms of transmission, such as voice communications or less reliable systems, might delay critical assistance. Therefore, utilizing Inmarsat-C TELEX is the most prudent method.

In contrast, using MF/HF voice directly to the RCC, while an option, may not guarantee the immediacy or reliability required in urgent distress situations. Similarly, other options could lead to complications in the communication chain, making them less favorable in this specific case. Thus, adhering to the