USA Today -- Airfares look to be on the rise again, with Southwest Airlines initiating a $5 each way hike on about 400 routes.

That represents about 10% of Southwest's routes. United Airlines quickly followed suit but expanded it to all domestic routes except for Hawaii.

American, Delta Air Lines, JetBlue Airways, Virgin America and US Airways also raised fares in select markets.

This is the industry's 13th attempt this year to raise fares. If successful, it would be the sixth airfare increase.

Typically when Southwest raises fares, others follow and the increase lasts.

"I have never seen a hike with Southwest participating that didn't stick," says RickSeaney, founder of FareCompare.com, which tracks fare increases.

Last year, airlines made 22 attempts to increase fares. Nine were successful.