"The accused Jitender Kumar Mohla is awarded life imprisonment under section 3(1)(d) of the Suppression of Unlawful Acts against the Safety of Civil Aviation," District Judge I S Mehta said.

The court, which had also convicted Mohla under sections 336 (endangering life or personal safety of others), 506 (criminal intimidation) and 170 (impersonating a public servant) of the Indian Penal Code, awarded him varying jail terms which were set off against the period spent by him behind bars since his arrest on February 2, 2009.

The court also imposed a fine of Rs 7,000 on him.

According to the police, Mohla had entered into the cockpit on February 1, 2009 and had sparked panic by claiming that he had hijacked the plane.

Mohla had also warned the crew members that he was one of the accused in the infamous Kandahar hijacking of an Indian Airlines plane in 1999 and was carrying needles with which he would "infect" others if they resisted him, it had said.

The crew members and some passengers, however, had overpowered Mohla and he was arrested the next day.

Police had said Mohla's behaviour had forced the Indigo pilot to send a hijack alert, leading to a scare and panic at the Indira Gandhi International (IGI) airport here.

The plane had made an emergency landing and was kept in isolation for two and a half hours after it was confirmed that the landing took place due to unruly behaviour of Mohla. The court, in its judgement convicting 45-year-old Mohla, had said he had intimidated the crew members by claiming to be an official of Directorate General of Civil Aviation (DGCA).

It had also said that Mohla was aware that his "terrifying act" would have endangered the safety of the 160 passengers and the crew members on board.

The court, in its judgement, had said every person on board a flight should observed certain "standards of behaviour" as per the norms laid down by the International Civil Aviation Organisation (ICAO) and the DGCA as India is a signatory to the Montreal Convention.

The court had, however, acquitted Mohla for the offence under the Anti Hijacking Act saying that nothing incriminating was found from his possession at the time of his arrest.