We know where they took off from and where they crashed but not where they were trying to get to. Was it just a pleasure trip to see the ranch/moon/stars on their wedding night or was he taking them to their honeymoon destination?
Either way, the fact he only made it a mile before crashing - an assumption since we don't know the exact time of the crash - leans heavily towards the disorientation of light into dark in an unstabilsed (I think) helicopter as a likely primary cause of this sad event.