Think the high price of gas is killing you? You can only imagine what it's doing to the airline industry. But if you've tried to buy a ticket recently, you don't have to imagine it. The struggling carriers are working overtime trying to survive economic turbulence that has nothing to do with mid-air flights. And your wallet is their only solution.

Most - including Air Canada - have already been forced to institute a fuel surcharge on the price of a ticket, as the costs of crude oil and gas continue to skyrocket and get passed on to travellers. And then earlier this week, American Airlines stunned passengers by announcing it would start charging US$15 for the first checked bag as a way to further raise revenues.

Now there are signs Air Canada may be looking to take that same route. The airline already added a Cdn$25 fee for a second bag but the move last week by its U.S. competitor reportedly has it at least thinking about upping the ante.

So far, the carrier says it has no immediate plans to take that giant step, but admits the soaring cost of fuel is taking its toll and that it has to consider all necessary measures to recoup ever increasing costs.

Its fee on second checked bags went into effect last month, a move met with instant customer outrage. Competitors WestJet and Porter Airlines have so far insisted they won't be following suit.

But that's a drop in the airplane bucket compared to what's coming next. On Friday,  three major U.S. airlines suddenly hiked their fees.  

United Airlines upped its ticket prices between $10 and $60. American Airlines added fuel to the fire (or in this case, fire to the fuel) by immediately following suit. Delta fell in line after that, making for a sudden spike in prices all passengers were fearing but no one was completely expecting all at once.

Each blames higher gasoline costs for the move.

All this has some experts worried that the industry itself is at risk, predicting more companies could go bankrupt if the crisis continues. "This is worse than 9-11," warns analyst Ray Neidl. After the terror attacks, "at least you knew passengers were coming back. Oil at $130 is unsolvable."

Many U.S. carriers have already instituted major layoffs and have been forced to raise fares a dozen times this year alone. American Airlines's fuel bill has gone up a staggering $3 billion since the start of 2008. And it's only May.

Advocates are warning that if the cost of air travel continues to reach new heights, passengers - whose own incomes are being squeezed by gas prices - will simply stop travelling and spend their vacations closer to home.

Some are already considering the idea. "Pretty soon you're going to be paying more for your luggage than to get to your destination," grumbles Roger French, who just returned to Boston from Hawaii.

And many are rethinking not only their travel plans but their luggage plans, too. "I would travel, but I probably wouldn't take a second checked bag," suggests passenger Robin Grossman. "I would try to carry on as much as I could."

But whether she'll be able to find an airline in the future that can 'carry on' in the face of ever higher costs is a question that - like the flights themselves - remains very much up in the air.