The Christmas holiday is typically a busy time for traveling, but this year more Americans are expected to stay home.Travel industry analysts, citing the fragile economy, forecast a substantial drop in air travel from last Christmas and a modest drop in car travel.In all, 63.9 million Americans are expected to take trips, down from 65.3 million last year and the lowest number since 2005, according to AAA, the parent of AAA Hoosier Motor Club, which conducts a widely cited annual survey.If the projections prove correct, this would be the first year since 2002 that Christmastime travel has not grown from the previous year.The airlines are expected to take the biggest hit: AAA foresees a decline of 8.5 percent; the Air Transport Association of America, an airline trade group, forecasts a 9 percent drop.It likely means a relatively quiet time at Indianapolis’ spanking-new airport, where from now through New Year’s about 21,000 travelers a day are expected to pass through.That’s still a big day for the airport — on a typical day, 14,000 passengers come and go. But it pales next to last year’s boom Christmas season when the daily average was 23,000.“We’re expecting it to be down the same as the national average,” said Susan Sullivan, an airport spokeswoman.“Thanksgiving was down, too,” said Rene Harris of the local office of the Transportation Security Administration, “but we don’t have the exact numbers.”Suzanne DeCellis, a Hoosier Motor Club vice president, said vacation travel during the holidays is still pretty strong, but then there’s that other kind of holiday travel.“I’ve seen a 5 to 8 percent downturn in going to Grandma’s,” she said.DeCellis defines “Grandma’s” as any non-resort city. “You’re booking Des Moines (Iowa) on Dec. 24, it’s Grandma, it’s family,” she said.The top vacation destination among Hoosiers: Disney World in Orlando, Fla.Among the many consequences of the travel slowdown: More than 100 people are expected at tonight’s Hanukkah dinner at Congregation Shaarey Tefilla in Carmel, even though the event falls during a school vacation. In better times, said Rabbi Arnold Bienstock, “a lot of these people would be in Florida.”More likely this year if they went anyplace, it would be within driving distance.About 52 million Americans, or 82 percent of all holiday travelers, intend to drive to their destinations.Still, that’s a 1.2 percent decrease from a year ago, according to AAA, and it’s happening despite plummeting gas prices — a gallon costs $1.30 less than it did this time last year.The season’s forecast is rosier for two far smaller players in the transportation sector.According to the AAA report, business for trains and buses will be up by 0.7 percent.Marc Magliari, a spokesman for Amtrak, declined to say what the rail operator anticipated, but noted that in November, ridership had dropped 3.6 percent.Locally, the most popular run is between Indianapolis and Chicago. Seats are still available, going in either direction, on Tuesday and Wednesday.Amy Wambaugh, a spokeswoman for Greyhound, declined to speculate on the number of passengers the bus line expected.“We just don’t know,” she said. “Most of our passengers buy their tickets on the day of travel.”