How can I request multiple airport codes when searching cities with multiple airports?

For example, for a BOM-LON search, how can I ensure the system searches all airports for London?

You must specify a valid airport or city code as the origin or destination. When you specify a valid city code as the origin or destination, that city code is automatically expanded to include all airport codes in that city. For example, when LON is sent as the city code, the system will automatically query all LON airports including LGW, LHR, LCY, STN, and LTN. If you specify LGW as the code, the system will only search LGW.

If you want to specify LHR as the destination and specify LGW and LCY as alternates on every origin and destination (O&D), you can do it with the following XML request snippet. However, this XML snippet will return one alternate location itinerary only if it is less expensive than the itineraries for LHR.

Example 1

<OriginDestinationInformation RPH="1"
                             <DepartureDateTime>2008-09-01T11:00:00</DepartureDateTime>
                             <OriginLocation LocationCode="BOM"/>
                             <DestinationLocation LocationCode="LHR"/>
                             <TPA_Extensions>
                                      <SisterDestinationLocation LocationCode="LGW"/>
                                      <SisterDestinationLocation LocationCode="LCY"/>
                                      <SegmentType Code= "O"/>
                             <TPA_Extensions>
                     </OriginDestinationInformation>

If you want to specify LHR as the destination, specify LGW and LCY as alternates. And, if you want to specify both globally for the whole request, you can do it with the following XML request snippet. However, this XML snippet will return one alternate location itinerary only if it is less expensive than the itineraries for LHR.

Example 2

</TravelerInfoSummary>
           <TPA_Extensions>
                    <IntelliSellTransaction Debug="0">
                            <RequestType Name="100ITINS"/>
                    <IntelliSellTransaction>
                    <AlternateAirportCities>
                           <SpecifiedLocation LocationCode="LHR"/>
                           <AlternateLocation LocationCode="LGW"/>
                           <AlternateLocation LocationCode="LCY"/>
                    </AlternateAirportCities>
           </TPA_Extensions>
      </OTA_AirLowFareSearchRQ>