TRENTON -- Five months after former Port Authority Chairman David Samson illegally strong-armed United Airlines into adding an infamous route to Columbia, S.C., Gov. Chris Christie and his son flew on the "Chairman's flight," NJ Advance Media has learned.

Christie, according to travel records, spent a little less than a week out of the state and took his non-stop flight from Newark to South Carolina on Sunday, Jan. 27, 2013. Along with his son Andrew Christie, the governor visited Samson, who, according to court documents, had encouraged others late in 2012 to take advantage of the Chairman's flight and visit.

Last week, Christie's office said the governor had no knowledge that he was piggybacking on United's political favor for Samson, whom the governor appointed to the powerful Port Authority job in 2011.

"No, the governor was not aware," Christie spokeswoman Jacqueline Halldow said in an e-mail.

Ultimately, the money-losing flight was the downfall of three United executives and Samson, who pleaded guilty last month to coercing one of the nation's largest airlines to accommodate his desire for a short-cut to his summer home.

Christie was never implicated in the criminal case against Samson. Nor was he the only notable passenger on the Chairman's flight.

David Samson talks with Governor Chris Christie in 2013

In fact, members of the U.S. attorney's office in New Jersey, which investigated and charged Samson, also took the Chairman's route, office spokesman Matthew Reilly confirmed last week.

U.S. attorney employees would sometimes take the flights to attend "the National Advocacy Center, which is attached to the University of South Carolina in Columbia, for specialized courses," Reilly said.

He couldn't say whether U.S. Attorney Paul Fishman or any of the assistant U.S. attorneys who prosecuted Samson flew the route. However, members of the office routinely flew to South Carolina for training and would board a Chairman's flight if the timing of the service fit their travel schedule, Reilly said.

United Airlines began running direct service flights between Newark and Columbia in September of 2012. The routes were dubbed "Chairman's flight" by Samson and also referred to by some as "Samson Air."

According to the court documents that charged Samson, United "decided on a weekly schedule that only included flights from Newark Airport to Columbia Airport departing at 6 p.m. on Thursdays (with a returning flight the same night) and from Columbia Airport to Newark Airport departing 6:20 a.m. on Mondays (after a flight to Columbia Airport the evening before)."

The collection of routes added by United had other weekend flights, including the Sunday flight Christie took. They never filled up and lost United an estimated $10,000 per week, and were all canned within days of Samson resigning as chairman of the Port Authority in March 2014.

Samson pleaded guilty to one charge of bribery for accepting a benefit of more than $5,000 from United Airlines and admitted that he "let it be known that the flight ... made it more convenient" for him to get to his home in South Carolina.

He also acknowledged that he took the flights about 27 times through 2013.

In November 2012, the month after the flights were created, Samson boasted about his route and encouraged an unnamed "consultant" to join him on his trip to his vacation home, according to court records.

"Heading south today?" the consultant asked, to which Samson replied: "Yes -- Chairman's flight -- Are you coming down for the weekend?"

The governor left New Jersey on Jan. 27, 2013 and returned on Jan. 30 by way of a non-direct flight. His trip included spending time with Samson. Christie, his son, and Samson were spotted at a horse track in Aiken, the town where Samson's vacation home is located. A photo of them was printed in a local newspaper.

In July, when Christie was first asked about Samson's guilty plea, he told NJ Advance Media: "He's my friend, and it made me very sad."

A day later, the governor said Samson made a "lapse in judgment."

Samson is scheduled to be sentenced on Dec. 13. He faces a maximum prison sentence of 10 years, but prosecutors are expected to recommend Samson receive no more than 24 months behind bars.

Matt Arco may be reached at marco@njadvancemedia.com. Follow him on Twitter @MatthewArco or onFacebook. Follow NJ.com Politics on Facebook.