Getting to meet the commander in chief of the United States left Airman 1st Class Tabitha Hriber at a loss for words.

"He just asked how I’m doing, and at that point all I could think of was, ‘Good,’" said Hriber, 24, one of about 50 service members who got a chance to bid aloha to President Barack Obama as he left Hawaii Tuesday morning for the next leg of his Asia-Pacific trip.

"It was amazing. My hands didn’t stop shaking until he boarded the plane," Hriber said as Air Force One taxied to the runway at Joint Base Pearl Harbor-Hickam.

The farewell wrapped up a four-day visit to the islands for Obama, who managed to conduct a 21-nation summit, hold bilateral talks with three major economic powers, speak at a fund­raiser and squeeze in a round of golf in that time.

It also caused one last traffic nightmare for Oahu commuters, who put up with road congestion for days as world leaders convened for the Asia-Pacific Economic Cooperation meetings.

Obama’s motorcade shut down roads Tuesday from Leeward to Central Oahu at the height of the morning drive as the president made his way to Hickam from the J.W. Marriott Ihilani Resort in Ko Olina, where he spent Sunday and Monday nights.

The caravan arrived at the airfield at 8:36 a.m. Obama, in light slacks, white shirt, blue blazer and no tie, worked the crowd for about three minutes, then exchanged greetings with Adm. Robert Willard, head of U.S. Pacific Command; Gen. Gary North, head of Pacific Air Forces; and Col. Sam C. Barrett, commander of the 15th Wing based at Hickam.

Service members at the departure represented all branches of the military and were chosen by their unit leaders for the chance to meet Obama.

"I think that my leadership knows what a great influence this could have on a young airman’s career, and I’m just lucky that I was the airman they chose," Hriber said.

Lt. Michael Zelinsky, who also got in a handshake with the president, was equally thrilled. "It was a really neat experience. Not many people get to do something like that in a lifetime, so it was pretty thrilling," said Zelinsky, 27.

Air Force One taxied away at 8:46 a.m. en route to Australia, where the president is scheduled to take part in more meetings aimed at strengthening the United States’ presence in the Asia-Pacific region.

The president is expected to announce that the U.S. is expanding its military presence in Australia by positioning equipment there, increasing access to bases and conducting more joint exercises and training. Obama then travels to Indonesia for additional meetings before returning to Washington on Nov. 20.

Obama joked during APEC that this trip marked the first time he ever had to wear a suit in the islands.

At his Monday fundraiser at the Disney Aulani Resort and Spa, Obama said he expects to be back in Hawaii for his family’s traditional winter vacation.

The Associated Press contributed to this report.