Sorry to resurrect an old thread, but does anyone have any insight into how much a lap infant is charged when an itinerary has these conditions:

* Premium Cabin Itinerary (Business or First)
* Route that UA does NOT operate (say HKG-JNB)
* Route that Multiple *A carriers operate [and not UA] (say SIN-ICN)

I understand the 10% of the full-fare applies, and is relatively easy to find out (without trying dummy tickets on .sux) for UA itins, but I cannot do the reverse engineering on these tickets from UA's crummy site.

If I knew how they were calculated, I could find places/routes that had relatively lower full-fare F/C fares and think about those for vacation, etc.

Thanks in advance if anyone has any insight!

-jeremy