Your assignment: Fly free with frequent-flier miles

The ability to book frequent-flier awards online has evolved substantially in the last year. These days, it is at least possible to book award travel at the major U.S. airlines' websites. But increased demand for a decreased supply of seats can make finding a ticket a frustrating exercise.

"I did interviews with the managers of the three top programs -- American, United and Delta," said Tim Winship, a frequent-flier expert and publisher of FrequentFlier.com. "They were totally in denial about the degree to which consumers are dissatisfied with the whole award availability issue."

I examined the online functionality at the six largest airlines with "traditional" frequent-flier programs.

I began with a simple premise: Most travelers have learned to be flexible when booking award travel. Thus, it behooves the airlines to provide them with flexible functionality to ease the process.

Here, then, is my ideal frequent-flier online functionality.

* It is easy to find the site to book award travel.

* If there are no flights for the dates I choose at the 25,000-mile award level, the website will tell me when there is availability. The more options, the better.

Airline sites just make me madder than a wet hen when they tell me, "Oh, well, we have no 25,000-mile awards available, but for 50,000 miles, no sweat." The promise is a free ticket at 25,000 miles. Help me find it.

So, here's a report card on the six largest U.S. airlines with this type of frequent-flier program.

American Airlines Aadvantage

Grade: A-

www.aa.com

The flight: LAX to New York. The dates I selected didn't have saver award availability. My search results showed the first dates for which saver awards were available after my date, plus return flights with the same number of days between them. Very neat stuff.

The good: Presents some smart options if saver awards aren't available.

The bad: Could provide more options.

Continental OnePass

Grade: A

www.continental.com