Following the lead of its competitor go!, Hawaiian Airlines said it will begin charging a $17 fee next month each way for checking in a second piece of luggage on interisland flights.

Go! airlines on Wednesday announced it was instituting a $25 fee for checking a second piece of luggage on interisland flights.

Hawaiian's fee applies to tickets purchased on or after July 8 for travel on or after July 15, 2008.

"Unfortunately, the impact of fuel prices on our operating expenses is forcing us to assess an additional fee for checking more than one bag," said Keoni Wagner, Hawaiian's vice president of public affairs.

"We want to encourage our customers to travel lighter as we do everything we can to reduce fuel use," he said.

The charge will be waived for several groups of Hawaiian customers, including HawaiianMiles Pualani Platinum, Gold and Premier Club members; corporate and affiliate members; and military personnel.

Checked luggage items exempt from the second bag fee include child car seats, strollers, wheelchairs, walkers, crutches and canes.