Sunday, May 6, 2007; P01

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Trusted travelers by this summer should be able to scoot through security lines at Dulles and Reagan National. Authorities for the airports have requested proposals, due this month, from companies that can operate a Registered Traveler program.

Airports in Cincinnati, Orlando, Indianapolis and San Jose -- and one terminal at New York's JFK, with another set to join it this week -- offer speedy lines in such programs, administered in each case by Verified Identity Pass and costing $99.95 a year. Members enroll online, then appear in person to offer up fingerprints, iris images and two forms of identification. VIP sends the info to the Transportation Security Administration, along with $28 of the fee the applicants have paid. Those approved by the TSA after a background check are given a "Clear" card providing access to special lanes, operated by VIP, that feed directly into TSA checkpoints.

VIP plans to open programs soon in Albany, N.Y., Little Rock and Newark. One other U.S. airport -- Jacksonville, Fla.-- has a trusted traveler program. It's administered by Vigilant Solutions, which charges $149 a year.

Frequent flier Henry Morgan of Orlando, who signed up the minute the program was offered in Orlando nearly two years ago, says it's "the best $100 I've ever spent." Morgan, who travels several times a month, told CoGo he used to arrive at the Orlando airport two hours before a flight. Sometimes he breezed through in 15 minutes, sometimes he barely made the plane. As a trusted traveler with a "Clear" card, he says, he's shaved an hour off his preflight arrival time: Although airline check-in times remain unpredictable, he knows it will take only four to five minutes to get through security.

Is it fair? It's no different from E-ZPass lanes, argues Morgan. Besides, he says, infrequent fliers who don't know procedures slow things down in regular lines, and "if you fly your butt off, you need an advantage."

Months after buying tickets well in advance on Air Canada, reader Marian Schwartz checked prices to see if they might have dropped. Sure enough, the exact tickets she held now each cost $93 less. She figured the airline would refund the difference. Surprise: Air Canada will not refund or credit any difference on a nonrefundable ticket, no matter how much the price drops.

"I'm certainly going to avoid Air Canada if possible" in the future, says Schwartz.

In fact, she wouldn't have gotten the $93 back from most airlines. The industry standard: If you point out a price drop, most airlines will credit you the difference minus a change, or "administrative," fee. Although such fees range from $10 to $100 for a domestic ticket, $50 to $100 is typical. Change fees for international tickets are up to $200.

In a survey of airline policies, CoGo found two notable exceptions. Southwest will give you a refund if the price of a same-class ticket drops, or a credit if a higher class of ticket goes on sale for less than what you paid. Jet Blue will give you credit for a future flight if a ticket in the same fare class drops. No charge.

If you're confused about whether the prices you're seeing as you shop are particularly high or low, check fare histories and predictions about where fares are headed at http://www.farecast.com. The Web site, under limited conditions, also sells, for $9.95, a kind of insurance policy that pays out if the site has predicted that fares will rise but instead they drop.

Demand for parking at Reagan National will be heavy from now through the end of the summer, particularly Tuesdays through Thursdays, airport authorities warn. Daily parking garages fill fastest in midweek, economy lots on weekends. Call ahead (703-417-7275) or check real-time parking availability at http://www.mwaa.com/. . . . Buy any Fodor's guidebook now through June 30 and receive a $100-off coupon on a five-night Expedia vacation package. Details  http://www.fodors.com/expedia.

Take a last-minute flight to South Africa for $1,239, including $216 taxes and fuel surcharge. South African Airways has the sale on nonstop flights from Washington Dulles to Johannesburg for travel through May 31. The fare is also available on connecting service to Cape Town or Durban (fuel surcharges and taxes vary). After May 31, fare goes up to $1,680. Fare on other airlines for connecting service to Johannesburg is $1,359. Purchase at www.flysaa.com.

Reporting: Cindy Loose

Help feed CoGo. Send travel news, road reports and juicy tattles to: cogo@washpost.com. By fax: 202-912-3609. By mail: CoGo, Washington Post Travel Section, 1150 15th St. NW, Washington, D.C. 20071.

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