Mile manager.

What's the best way to improve my chances of getting a seat upgrade using frequent-flier miles?

According to Theo Brandt-Sarif, publisher of Traveltactics.com, you should manage frequent flier miles as carefully as you oversee an investment portfolio. "Used judiciously, they can help you maximize first-class benefits at the lowest possible costs," says Brandt-Sarif. One key strategy: Try to fly one airline and its partners to eventually qualify for the program's top frequent-flier status. Your upgrade requests will get higher priority, and you will be able to go first class for free or for a fraction of the flail fare. Second, don't use frequent-flier miles to fly coach or even first class between U.S. destinations that already offer great deals. Save the miles for longer and more expensive international trips. Last, consider buying discounted first-class tickets to rack up bonus miles faster. The price of some roundtrip business and first-class seats have dropped up to 75% during the last six months, says Brandt-Sarif.

Newer planes are flying greater distances than ever. What is the current longest commercial flight in the Americas and what does it cost?

It's hard to say exactly, but it likely runs from Canada to Chile. Air Canada has a flight from Toronto to Santiago, and it is probably the longest at 11 hours, says Barry Hough, an airline consultant for AvGroup. A roundtrip flight costs US$1,012. Chilean carrier LAN and others fly across the hemisphere from Los Angeles to Buenos Aires, but they often stop in places like Lima. Other carriers rely on hubs serving the hemisphere. American Airlines, for one, operates from Miami International Airport. "There are a lot of miles and not long-haul flights," says Hough. If 11 hours on a plane sounds rough, then get a load of this: Singapore Airlines last year claimed to service the world's longest non-stop route, between Singapore and Los Angeles, an 18-and-a-half-hour-long flight on an Airbus A340-500. The company says that the long route will save passengers six hours they would otherwise lose on stopovers. That flight costs $1,242.

More superplanes are coming. In March, U.S. aircraft manufacturer Boeing tested its 777-200LR Woddliner, a plane that it claims will be the world's longest-range commercial flight by carrying 301 passengers for 9,420 nautical miles, a 19-hour trip. Don't expect to see it over Latin America's skies any time soon. The first delivery to take place will occur in January 2006 to Pakistan International Airlines. "I believe the stated intention of the first customer in Pakistan is to fly it to the United States, more than likely in the Southwest or West Coast," says Boeing spokesman Marc Birtell.

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