Payloads can be considered somewhat independent from the RPAS in that the main focus is to deliver safe, economically efficient RPAS which are fit for task. This is analagous to a bus being fit to tavel on public roads whether or not it is carrying passengers. Therefore any RPA and RPAS must be capable of carrying the required payload(s) safely and efficiently. Equally, any payload should not detract from the safety of the RPAS to an unacceptable degree (ie the need to stay within safety target tolerances). Issues such as damaging payload substances/liquids, communications interference or other disruptive electonic emissions and over-heating can all endanger safe RPA navigation.
While the payload operation may be controlled from a RPS, some system architectures/configurations involve a separate control station for the payload, which is very likely to require additional communications with the RPS.
With some small RPAS, the payload communications may share the flight control communications in a multiplex arrangement. This has implications for communications integrity and security, in addition to airworthiness.
Further Reading
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