My family is planning a summer holiday in the USA in the summer of 2009. I've tried to find flight tickets that allow us to fly more or less as much as we want within a specific time period ­ three weeks would suit us. Do you know of any company that sells such tickets? Stein Eliassen, Norway

Sunday Times travel expert Richard Green responds: You are thinking of an "airpass". They were popular before the days of the no frills airlines, when US domestic air fares were very expensive - unless you could fit in with lots of annoying cheap fare rules, like always having to make a return flight and ensuring that your stay was over a Saturday night.

They are still around, but they just aren't very good value any more. Delta, Continental and Northwest are all in the Skyteam Alliance for example, which has a pass starting at about £350 ($559) for any three flights in the US ­ plus about £63 ($100) for each extra one. Note that you have to fly across the Atlantic with a Skyteam airline to qualify.

Now there is so much competition from the low fares airlines, the traditional carriers have ditched their arcane fare rules and slashed prices to try and stay in business. Delta Air Lines for example, has non-stop flights from LA to New York for less than £90, and shorter flights for under £50.

So I'd say that you are better off using the Internet to book your flights with a search site like Ebookers, Kayak, Skyscanner, Expedia, or Travelocity, all of which have international sites in local languages, including Norwegian. Or contact a travel agent that specialises in such trips, like Trailfinders, Travelmood, or Travelbag.

Attitude Travel is a good way to find some US no frills airlines, which aren't always featured on the above websites.

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