(Updates paragraphs 1-8; edits)
By Michael Conlon
CHICAGO, Nov 27 (Reuters) - Amid tight airport security but generally friendly weather, millions of Americans took to the roads and the air on Wednesday to meet family and friends for the Thanksgiving holiday, the busiest four-day travel period of the year.
A storm dumped up to 10 inches (25 cm) of snow on parts of New England and slowed traffic at all levels in Massachusetts, but that was the only major trouble spot. Despite crowded airport roads and choked parking lots, check-in delays at major airports ranged only from an hour to none at all.
"I heard it was going to be really busy, with people lined up all over the place," said Richard Orapollo who arrived two-and-a-half hours early at Washington's Reagan National Airport for a short-haul flight to Syracuse, New York.
"When I arrived it was fine," he said. Hours later the airport still had lines that took no more than 10 minutes to pass through.
Post-9/11 security measures and sheer traffic volume did mean delays inside other airports, however.
At mid-afternoon it was taking an hour to get through security and baggage check-ins in the main terminal at Denver's airport and in terminals three and eight at Los Angeles International, according to Travelocity, the online booking site which sent monitors to 25 major airports.
At Los Angeles International motorists found it took up to 30 minutes to get to their terminal from the airport entrance as traffic on the airport loop road was at a standstill, cars unloading passengers at times occupying three of the road's five lanes.
In terms of air traffic and delays "for the most part everything is looking good nationwide," said Brian Bicek, air traffic management specialist for Orbitz, another online travel booking company. "Everything is running smoothly."
He said Boston's Logan International was operating with one runway while it cleared snow from the others, resulting in half-hour delays. He also said gusty winds which caused traffic delays in the Chicago area earlier in the day could cause similar problems later on Wednesday along the East Coast.
At Dallas/Fort Worth International Airport "the lines are short and brisk," said spokesman Ken Capps. He said the average wait time to pass through security checkpoints was six minutes, well below the airport's goal of 10 minutes.
BANDS ENTERTAIN TRAVELERS
The airport hired about 100 "holiday helpers" to hand out coloring books and crayons to children and giving soft drinks, popcorn and cotton candy to families.
Bands played in busy terminals at Chicago's O'Hare and a touring group of New York's famous Rockettes handed out candy canes.
Passenger lines at Boston's Logan were lighter than normal as many travelers, fearing complications from the weather, arrived early. Some even changed their travel plans and left on Tuesday night.
Massachusetts State Police reported minor fender-benders on state highways and said some motorists had driven off roads because of the snow, which averaged between three and six inches (eight and 15 cm) across much of the state.
In general flight delays were scattered and minor, according to the Federal Aviation Administration.
Aircraft de-icing from Cleveland, east through New York state and into New England caused minor problems on the ground. Boston's Logan also reported some delays because of de-icing.
Even though more people were expected to be flying than a year ago, airlines did not add a significant number of flights because they have already cut schedules to save money during the industry's worst downturn.
CROWDED TRAINS
Dan Stessel, an Amtrak spokesman, said service on the rail line's flagship Northeast Corridor between Washington and Boston was running smoothly despite the New England snow.
Amtrak added 58 trains to its Northeast schedule between Tuesday and next Monday and added more cars on some trains. In all it said it expected 310,000 riders in the corridor during the holiday period, about 30 percent higher than normal.
The American Automobile Association had estimated that 35.9 million Americans would travel at least 50 miles (80 km) over the four-day period, a 1.7 percent increase over a year ago. But even with the rise the shadow of terrorism was still evident -- this year's figures were nearly a million below pre-9/11 levels.
Most of the travelers -- 30.8 million -- planned to go by car. But the AAA said 6 percent more people were flying this year than last.
A 6 percent increase in air travel was also predicted by Maritz Hospital Research Group, based on a poll of more than 1,000 adults; but it disagreed with the AAA, saying its survey found that only 28 percent of Americans said they would travel this holiday, down from 33 percent a year ago.
Sunday -- when travelers who left on various days the week before all try to return home at once -- is traditionally the single busiest U.S. travel day of the year.