- The crew's reliance on AINS resulted in plane hitting mountain
Not sure what exactly you mean be "reliance" in this context. Are there some other words you can use instead?
The aircraft was being navigated visually at the time of the accident.
Using my understanding of that word, I would say that the crew were reliant on the AINS for the overwater segments, but as Cape Hallett came into sight, they became less reliant on it. The "reliance level" continued to steadily decrease from then on.
-It follows that reliance on AINS is not a substitute for ground aids.
Agreed, and I don't believe anybody in this thread has stated anything to the contrary.