A Montreal woman who uses a wheelchair and needs a travel companion to fly says she's upset two major Canadian airlines are fighting a court decision that would allow her assistant to board for free.

Natalie Cinman, 25, has a genetic brittle-bone disease and must be accompanied by an assistant when she flies because she needs assistance to settle into her seat and travel comfortably.

Her travel companion may have to pay for a seat if Air Canada and West Jet are successful in fighting a Federal Appeals Court decision in May that upheld a ruling from the Canadian Transportation Agency requiring airlines to provide "one person, one fare" for people with disabilities. Airlines were given one year to comply with the ruling.

Both airlines filed a request with the Supreme Court of Canada in August to appeal the federal decision and agency ruling, which applies to passengers required to travel with an attendant because they are functionally disabled, or obese and need two seats.

Cinman, who flies frequently for work, said the airlines are being unreasonable.

"I can understand why any business wouldn't want to offer a free seat to a customer, but they have to understand that the person coming along with the disabled person isn't just coming along for the free ride," she told CBC News this week.

"They have a job to do, and that's to take care of the person they're travelling with. This person relies on them."

Cinman is concerned about the onus being placed on flight attendants who already have work to do on board. "I don't think the flight attendants are able, or want to be liable, to be taking care of disabled persons," she said.

There's also a matter of trust, Cinman said.

"I prefer it be somebody I know, nor do I think the flight attendant is trained or who wants to be liable to start picking up people, lifting people with special needs."

There is no doubt some people need to travel with a companion, but it's unclear whether airlines should bear the additional cost, said Karl Moore, an aviation industry analyst and professor at the Desautels faculty of management at McGill University.

"I would understand, it's going to cost them some profitability, [but] the question is how many people would it apply to?" he asked.

"If someone is going to require that someone else has to travel with them … I think there is a responsibility that someone other than the airline [pays], and if it's someone that's poor, perhaps the government [has a role to play].

"But I don't think it's a fair burden on the airlines to give a free seat to someone else," he said.

The Supreme Court of Canada will hear Air Canada and West Jet's appeal in 2009.