A dual US-Iranian citizen has apologized for exporting sensitive information about US military jets to Iran, saying he was simply applying for a job, before a judge sentenced him to eight years and one month in prison.

Mozaffar Khazaee, who had worked as an engineer at US defense contractor Pratt & Whitney, was arrested in January 2014 as he tried to leave the country with sensitive material about the engines for the US air force’s F-35 Joint Strike Fighter and F-22 Raptor aircraft in his luggage.

Khazaee had also exchanged emails containing information about the programs with Iranian contacts, according to court papers. He said the emails were part of a job application.

“I never sold anything to anybody,” Khazaee, 61, told the court, standing hunched over and reading from notes. “Had I known that making a PowerPoint presentation to an Iranian university in my attempt to get a job was breaking the law, I never would have taken the documents at all.”

US district judge Vanessa Bryant said she was unimpressed with his assertions about emails relating to his previous employer, a unit of diversified manufacturer United Technologies Corp. The company had laid him off in 2013.

“He not only minimizes his criminal conduct but genuinely fails to understand the significance of his actions, and that is especially troubling,” Bryant said.

The sentence she imposed, which included three years’ supervised release, was less than the 10 years prosecutors had sought.

The US Arms Export Control Act limits the export of information related to weapons systems.

Federal prosecutors contended that Khazaee’s description of that exchange was inaccurate, saying he had emailed information on the jets well before being laid off and that he had told a contact in Iran in an email the information he sent was “very controlled … I am taking big risk.“

His 85-year-old mother, who spells her name Molok Khazaye, had asked in a letter to the court for leniency for her son.

“I have no protector other than [my son] and am depend on him financially and emotionally strongly so,” the defendant’s mother wrote. “I kindly request you to grant him a pardon due to his mistake.“

Khazaee’s brother and sister had also asked for his release.

Before his time at Pratt & Whitney, which makes jet engines, Khazaee worked at major manufacturers including General Electric Co, according to court papers.