WASHINGTON — Testing for a new program aimed at getting certain travelers through airport security with less hassle has gone so well that the Obama administration plans to expand it to another round of airports and travelers, the government said today.

The expanded testing will not affect most travelers expected to crowd the airports during this year’s busy Thanksgiving travel season. But the government has made other changes in the past year that could make for a less intrusive trip through airport security.

Invasive pat-downs and full-body imaging machines are still a central part of the air traveler’s experience in the U.S.

But now children 12-and-under are less likely to be patted down or forced to take off their shoes. And about half of the full-body imaging machines have been upgraded to show an outline of a person instead of a blurry naked image.