Pilot Clayton Osbon, who had been charged with interference with a flight crew and could have faced up to 20 years in prison, was found not guilty by reason of insanity in July.

U.S. District Judge Mary Lou Robinson ruled that a court-ordered evaluation of Osbon, which was to have been completed this week, be extended until October 15.

Robinson said she was notified last week of the psychotic episode by a forensic psychologist at a federal medical centre where Osbon was sent for testing, court documents show.

The psychologist requested the extension of the evaluation period, which Osbon's lawyer and federal prosecutors agreed to.

The nature and duration of Osbon's psychotic episode in prison were not disclosed in court documents.

Robinson, following a brief bench trial last month, ordered federal examiners to prepare a report on Osbon's mental state, with a view on whether his release would create a "substantial risk of bodily injury to another person or serious damage to the property of another."

Robinson will use the findings of that report to determine Osbon's sentence. She could order Osbon confined to a secure mental facility or released from custody.

Osbon, 49, was charged with felony interference with a flight crew after he began ranting incoherently as he piloted a JetBlue flight from New York City to Las Vegas on March 27.

The first officer on the flight told the FBI Osbon had told him "we're not going to Vegas" and began talking about Iraq, Iran and al-Qaeda.

After the first officer got Osbon off the flight deck, passengers said Osbon ran around the cabin screaming until flight attendants and passengers managed to subdue him.

The plane made an emergency landing in Amarillo, Texas. (Editing by Corrie MacLaggan, Cynthia Johnston and Todd Eastham)

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