SINGAPORE - An Indian national was jailed for nine months on Wednesday for molesting a flight attendant on board a SilkAir flight from India to Singapore.

Kizhakkumkkara Thomas Ajeesh, 31, admitted to using criminal force on a 26-year-old cabin crew member by brushing against her chest during a flight from Trivandrum to Singapore on Sept 9.

He also pleaded guilty to being drunk to an extent where he jeopardised the order and discipline required on board a plane.

The court heard the plane departed from Trivandrum, India, at about 1.15am.

As soon as the seatbelt sign went off, Kizhakkumkkara asked for alcoholic drinks and was served four glasses of whiskey. He became tipsy and the cabin crew member decided not to serve him any more alcohol even though he badgered them for more. He even went to the back galley to ask the cabin crew for alcohol but was rejected.

A passenger seated in his row successfully asked to change his seat as the accused's actions of constantly heading back to the back galley started to annoy him. At about 4am, the seatbelt sign was turned on but the accused's seatelt was not fastened. The victim told him to buckle up but he repeatedly refused, and continued instead to ask for alcoholic drinks.

She refused and insisted that he fastened his seatbelt, which he did eventually.

When the victim turned to go back to the back galley, the accused stretched his hand and brushed against her breast. She screamed and told him not to touch her.

The accused could have been jailed for up to two years, fined, caned or received any combined sentence for outrage of modesty.

The penalty for the offence under the Air Navigation Act is a $20,000 fine and 12 months' jail.