Seattle, Washington (CNN) -- Over the last four months, Colton Harris-Moore has kept busy in solitary confinement by designing airplanes, his attorney said Thursday.

But it may be years before the so-called "Barefoot Bandit," accused of stealing and flying airplanes without a pilot's license, gets anywhere near aircraft again.

Harris-Moore, 19, pleaded not guilty in a Seattle courtroom Thursday to five federal charges, including transporting a stolen aircraft, transporting a stolen firearm and flying a plane without a license.

Four of the charges are punishable by up to 10 years in prison and a $250,000 fine. Flying a plane without a license carries a possible three-year sentence.

A January 18, 2011, trial date was scheduled.

Harris-Moore, 19, earned the nickname "the Barefoot Bandit" for an alleged multistate crime spree that authorities say involved stealing and crashing as many as five small planes, sometimes while not wearing shoes. Federal prosecutors have said he could be behind as many as 100 crimes, ranging from stealing cars and boats to burglarizing homes and committing online identity thefts.

Harris-Moore had been on the run since 2008, when he disappeared from a Washington-state halfway house after pleading guilty to three counts of burglary.

He was arrested in the Bahamas in July after allegedly piloting and crashing a stolen plane there. The plane went missing in Indiana, more than 1,000 miles away. His dramatic arrival in the Bahamas garnered international headlines and set off an island-hopping manhunt. Bahamian police arrested him after shooting out the engine of a boat he allegedly stole.

Despite his notoriety and social media sites dedicated to his alleged exploits, Harris-Moore kept a low profile in court Thursday. Wearing a khaki uniform with a bright orange undershirt, Harris-Moore, who is 6 feet 5 inches tall, sat hunched in a chair behind his attorney.

His eyes were fixed on the ground and three U.S. marshals stood in a circle around him for most of the five-minute long hearing.

Harris-Moore looked up and spoke only when responding to Magistrate Judge Mary Alice Theiler, who asked him to say his name and his year of birth for the record. Defense attorney John Henry Browne entered the plea of not guilty for his client.

After the hearing, Browne described Harris-Moore as "shy and naïve. He's never done drugs or had a sip of alcohol."

The captured teen fugitive, Browne said, spends his incarceration reading mail sent to him from around the world and studying airplane design.

Despite reports of book and movie projects underway, Harris-Moore had no interest in profiting from his story, Browne said, unless proceeds could be used to compensate his alleged victims.

Browne said he was engaged in "productive" discussions with the U.S. attorney's office in Seattle to consolidate the federal and state charges, which could include as many nine states and several Washington-state jurisdictions.

Emily Langlie, a spokeswoman for the U.S. attorney, said Thursday that the office does not discuss plea negotiations.

Some of the jurisdictions where Harris-Moore faces charges have already agreed to waive prosecuting him, Browne said, for a possible deal that would involve his client serving jail time and paying restitution. Browne would not identify the prosecutors in favor of the deal, but said he hoped an agreement could mean Harris-Moore might serve as little time as four years in prison.

"If everyone doesn't agree to consolidate then it will mean quite a bit of trials," Browne told reporters. "Then I'll bankrupt them," he said referring to counties that choose to prosecute Harris-Moore individually.

"What a blowhard," Island County prosecutor Greg Banks responded when told of Browne's comments to the media. "We haven't heard from him, maybe he doesn't think we have telephones here."

Island County includes Camano Island, where Harris-Moore grew up and faces at least a dozen charges for alleged identity thefts, burglaries and driving a stolen car. Banks said he believed that forensic testing could lead to more charges being filed soon.

Banks said he did not expect a trial would be particularly complicated or costly for the county to hold.

The prosecutor also said he doubted that the proposed federal deal to consolidate charges could be applied to the state level and that a separate agreement would have to be struck among the Washington-state counties where Harris-Moore faces charges.

"But the justice system is more than just about counting up years," Banks said. "He has to be held accountable for what he did here."

CNN's Patrick Oppman contributed to this report.