I use the Great Circle mapper at http://gc.kls2.com/

It's sometimes "off" by a mile or two than what a specific airline will credit, but it's close enough in most instances.

JFK-LHR r/t is 6902 miles (AA credits 6904, to give an example). That gives you 3098 miles to play around with. As ozstamps mentions, that gives coverage to a _whole_ lot of cities in Europe.

Just be careful to figure in any open jaws.

For example, I posted elsewhere that I'm flying JFK-LHR-TXL (open Jaw) VIE-LHR-JFK (well, when I posted I was going to fly EWR-JFK, but I felt the urge to fly Concorde in both directions because I couldn't get a 747 from JFK on the outbound).

my calculations:
----------------------------------
- TXL-VIE is going to be ground,and my reading of the rules is that the miles for the ground segment are added in, so:
EWR-LHR 3465
LHR-TXL 590
TXL-VIE 340 (open jaw)
VIE-LHR 794
LHR-JFK 3451
TOTAL 8640
----------------------------------------

Over 1000 miles "wasted"! [Gasp!]

I, too, was looking into how far beyond London you could get on these awards- by my math, however, some of the destinations mentioned are outside the range from JFK-LHR- Moscow comes in at 10,046 for me; IST at 10,030. Is my math off, or is there a grace allowance above 10,000 miles? Of course, one could fly BOS-LHR in F if these destinations were more important than flying Concorde.

But the point is well-taken that the award will get you to some expensive destinations onward from London, and the taxes for tickets beyond are usually (aways?) cheaper than tickets JFK-LHR.



[This message has been edited by landspeed (edited 06-16-2002).]