Say goodbye to $39 airfares.

Citing rising fuel costs, discount airline go! raised its standard interisland ticket price by $10 to $49 earlier this week, prompting competitors Hawaiian Airlines and Aloha Airlines to match.

The fare hike is go!'s first since its June 9, 2006, launch, which kicked off a protracted interisland fare war.

The $39 one-way tickets were welcomed by local consumers, who have saved tens of millions of dollars. The low fares also increased the volume of travel between O'ahu and the Neighbor Islands.

But the pricing was tough for the airlines. Aloha said earlier that it loses money anytime fares dip below $50.

Local aviation industry historian Peter Forman said the $49 fare is still a good bargain.

"This fare can be sustained much longer than a $39 fare," Forman said.

Prior to go!'s 2006 entry into the Hawai'i market, one-way fares were in the $70 to $90 range.

"It's still a fare war," Forman said. "This thing is not resolved by any stretch, but at least the deep, deep losses will lessen and we can have much more sustainable fares."

Still, many travelers will miss the $39 tickets.

"This is going to be a hit to all of us," said Barbara Hastings, a public relations executive who lives on the Big Island. "During this period of lower fares, I've flown over (to O'ahu) and back on the same day often. Now, I think I will do less of that."

go! said the fare increase was due in part to rising fuel costs.

"Fuel costs rising over $100 a barrel combined with recent court decisions have forced us to increase our fares by $10," said go! spokesman Joe Bock.

In October, a federal bankruptcy judge ordered Mesa Air Group, the parent of go!, to pay Hawaiian $80 million for misusing confidential business information.

Bock said the $10 increase is not a fuel surcharge that will go away when fuel costs ease.

The $49 fare will be go!'s new standard fare, although go! will continue to offer special discounts such as the $19 and $29 fares when the occasion warrants it, Bock said.

Both Hawaiian and Aloha have suffered steep losses in part due to the low interisland fares.

In recent court testimony, experts for Hawaiian estimated that the carrier is losing between $40 million and $50 million as a result of the fare war.

Privately held Aloha has not disclosed results from the interisland market but its losses are likely to be comparable to that of Hawaiian since its market share is close to that of Hawaiian.

The fare increase is the latest setback for Phoenix-based Mesa Air Group.

In a filing with the Securities and Exchange Commission yesterday, Mesa disclosed that it may be subject to delisting by the Nasdaq stock exchange for not filing its year-end and quarterly financials on schedule.

Last month, Mesa said it will delay the filing of its financials until Jan. 15 due to complications over its reviews of estimates and reserves.

Brian Gillman, Mesa executive vice president and general counsel, said he anticipates that the company will file its financials with the SEC on or by Jan. 15, or well before any delisting proceeding.

Shares of Mesa closed at $2.70 on the Nasdaq market, which was up 2 cents from Thursday's close. Since the June 9, 2006, launch of go!, Mesa's shares have fallen more than 69 percent and the company's market capitalization has dropped by more than $179 million.

Reach Rick Daysog at rdaysog@honoluluadvertiser.com.