Passengers on an international flight from Thailand have spent more than six hours stranded on the plane at Alice Springs Airport, after it was forced to land due to a passenger suffering a medical emergency.

Jetstar flight JQ30 was travelling from Bangkok to Melbourne when it was forced to land at the domestic airport at about 7.20am (ACST) on Sunday. While the aircraft was on the tarmac, an electrical fault was detected which a Jetstar spokesperson said required a replacement part to be sourced from Sydney. 

The passengers were stuck on board the plane for almost seven hours while Jetstar attempted to arrange permission for them to disembark. 

"As a domestic airport, Alice Springs does not have customs processing facilities and we've been working with Border Agencies, the NT Police and the local Airport Authority on the best way to support customers until that replacement aircraft arrives," the spokesperson said on Sunday. 

With the plane suffering air conditioning issues and the on-screen entertainment switched off, passenger Paul Tarrant said the mood onboard was "getting a little bit crazy" as they waited to leave the aircraft. 

"I must say, the staff have been friendly and tried to make the best of the situation, but there's sick people on board, we've been here for a hell of a long time and it's not getting any better," he said. 

"It's getting pretty bloody hot inside as well."

Passengers were finally given the option to disembark "into a specially partitioned section of the airport" at about 2.15pm on Sunday, as they waited for a replacement aircraft to arrive.