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On the routing itself there are the following issues/comments:
No CX flights to Vietnam can be used on a OWE. See Q1
The x transit in HEL is irrelevant except to the tax issue. If you are really only in transit then why not PEK-LHR on BA and then an extra segment somewhere else (e.g. LHR-EDI-CDG)
The transits in NA are irrelevant except to the tax issue. for MAI I assume you mean MIA.
I assume SCL-LAX-SYD is to maximise miles? Otherwise you can go SCL-SYD on LAN Chile.
<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by momo35:
Q1 : I've just heard that some flights are not available for OWE (e.g. CX flights between Vietnam and HKG). Does anyone know where I can find a list of those flights ?</font>
See the full list of the OWE rules through
http://fewmiles.net/oneworld/owe.html
lines 24-33.
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Q2: Is there a big difference in terms of taxes between a connection and a stopover ? I've read some posts about HKG, but does anyone know about LHR and SCL ?
(I know taxes in LHR are quite expensive and I'm thinking of making a connection in lhr, instead of a stopover on my way to cdg).</font>
See:
http://www.consolidatedtravel.com.au/qf/taxes.asp
which shows that in Chile, for example, there is a significant saving for transits of less than 6 hours. Whether you could get anyone to ticket it without the charge given that even with an X the ticket would allow you up to 24 hours is anouther matter.
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Q3: I've read in many posts that it's better book the first segments, leave the other ones Open, and book when needed.
Can the reservation be done at any OW desk in any airport ? Do they charge an "administration fee" for this ? Do it depend on which company ticketed the OWE ?
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The easiest way to do this I find is to get a tame travel agent. But you should also be able to call any OW reservations desk and get them to do it for you at no charge.