A Colorado couple who reported their son was aboard a runaway balloon could land in jail after pleading guilty Friday to charges they made up the story to generate publicity for a possible reality TV show.

Richard Heene appeared before a Larimer County District Court judge first, pleading guilty to a felony count of falsely influencing the sheriff who led the rescue effort during the 80-kilometre balloon flight across northern Colorado that captivated a global television audience on Oct. 15.

Mayumi Heene, who is a Japanese citizen, pleaded guilty to a misdemeanour charge of knowingly filing a false report with emergency services. Prosecutors said she had a lower level of culpability and co-operated with authorities, telling investigators the balloon launch was a publicity stunt two weeks in the making.

The Heenes are amateur storm chasers and had twice appeared on the ABC network's reality TV show "Wife Swap." Richard Heene's business associates said he was trying to pitch a TV series based on science, and the couple had a tentative deal in the works with RDF USA, which produces "Wife Swap."

RDF has said it scrapped the plans after the balloon flight.

Even as the Heenes entered their guilty pleas, their attorneys' comments in court set off speculation of talk show appearances or other deals.

Judge Stephen Schapanski agreed to the attorneys' request that the couple be allowed to travel to New York and California to explore "employment opportunities." David Lane, Richard Heene's lawyer, declined to elaborate as he left the courtroom, and Heene waved off questions.

At least one New York-based production company ruled out a Heene venture.

"It's just too poisonous," said Irad Eyal, vice-president of development at True Entertainment. "I don't think anyone is going to want to meet with a man who shamed his family and children that way. In reality TV, there's a definite line you don't cross, and that's tormenting children."

Lane said the couple would have no public comment at least until sentencing, set for Dec. 23.

Under terms of the plea agreements, Richard Heene faces up to 90 days in jail, probation and a fine. Mayumi Heene could get 60 days, likely to be served in a work-release program, and probation.

Richard Heene also could have to pay restitution for tens of thousands of dollars in costs incurred by police.

Without the deal, the charge against Richard Heene carries a possible sentence of two to six years in state prison and a fine of up to $500,000. The charge against his wife is punishable by up to six months in the county jail and a fine up to $750.

The deal does not call for removing 6-year-old Falcon or the couple's other two children -- boys ages 8 and 10 -- from the parents' custody, according to Lane.

Larimer County Sheriff Jim Alderden has said the Heenes deliberately released the balloon and falsely reported Falcon may have been inside. The boy was later found safe at the Heenes' home.

A global audience watched in horror when the balloon landed with no sign of the boy inside. The reaction turned to anger at his parents when authorities days later accused them of perpetrating a hoax.

The story began to unravel when Falcon Heene said they "did it for the show" during a CNN television appearance.

Investigators found evidence Oct. 17 that the Heenes were working with RDF on a reality show, according to court documents released Friday. It wasn't clear when RDF's plans were scrapped, or if the company knew anything about the couple's plan to release the balloon.

RDF didn't immediately respond Friday to phone and email requests seeking comment.

Sheriff's spokeswoman Eloise Campanella said Friday some aspects of the case were still under investigation. She would not comment on RDF.

Lane portrayed his client's decision to enter a plea as a sacrifice to preserve the family and avoid the possibility that Mayumi Heene could be deported by being convicted of more serious charges.

Lane said prosecutors threatened Mayumi Heene with that prospect. But chief deputy district attorney Andrew Lewis insisted Friday that prosecutors never did so.

Richard Heene was asked after the hearing if he had anything to say to those who looked for his son. He didn't respond.