Delta Air Lines' nonstop Pittsburgh-to-Paris flight isn't hitting its revenue targets, likely leaving state taxpayers and a local economic development agency on the hook to make up the difference.

And unless more people start taking the flight, the region could be in danger of losing it altogether by June 2011 when state and private subsidies end, officials warned.

In a report Friday, the Allegheny Conference on Community Development said a plunge in fares caused by the global economic crisis is the chief reason the flight, which started last June 3, is not making enough money to meet projections.

As a result, the conference anticipates it and the state will have to pay the maximum $5 million, with each responsible for half, pledged to offset revenue shortfalls in the first year of the flight's operation.

Both could end up paying up to $4 million in subsidies in the flight's second year if its performance does not improve. The subsidies are part of an agreement with Delta that led to the launch of the service last spring, Pittsburgh's first nonstop transatlantic connection since November 2004.

The conference, in a report to the Allegheny County Airport Authority, said the flight sold 68 percent of its available seats in the first eight months of operation. That was within the forecasted range and would have been enough to avoid subsidies were it not for the sharp drop in ticket prices, the report said.

In projections for the flight, the conference used a one-way ticket price of $582, which it said was the average Pittsburgh-Paris fare for early 2008, based on U.S. Department of Transportation statistics.

But by the third quarter of 2009, the one-way fare had plummeted to $413, down 31.6 percent from the same quarter in 2008. The conference blamed the global recession, saying it had reduced transatlantic traffic industrywide and forced down fares.

The report indicated the decline in ticket prices is not unique to Pittsburgh, pointing out that at the beginning of 2010 premium fares throughout the industry remained more than 35 percent below early 2008 levels.

In addition, the International Air Transport Association estimated this week that the global airline industry lost a combined $25.3 billion in 2008 and 2009, worse than the losses after the Sept. 11, 2001, terrorist attacks, according to the report.

"Had air fares remained stable at the 2008 level with that 68 percent load factor, which is low for a flight, we would be exceeding our revenue targets," said Ken Zapinski, the conference's senior vice president of the transportation and infrastructure program.

Nonetheless, the conference report noted the 68 percent load factor for Pittsburgh to Paris trailed the average load factor in Delta's transatlantic network by 12 to 18 points.

Based on third quarter 2009 federal data, an average of 407 passengers each day flew from Pittsburgh to a destination in Europe, the Middle East, India or Africa or vice versa. Of those, 21.6 percent chose the Delta nonstop flight.

In its report, the conference said the flight will be "at risk" next year if business, leisure and academic travelers do not make it their "preferred choice" for travel to Europe and other destinations.

"If we don't use this [flight], we will lose it. It's simple economics. It's not complicated," said Glenn Mahone, airport authority board chairman.

"The second year of the Delta flight will be crucial to maintaining the Delta service. While we hit load targets in the flight's first year, to keep the flight we must do even better in the second year because of the severe and unanticipated drop in global air fares caused by the recession," said Peter Kalis, global managing partner of the K&L Gates LLP law firm and chair of the conference's transportation and infrastructure committee.

In an effort to boost traffic, the airport authority has begun marketing the flight in Cleveland and northeastern Ohio, which has lost nonstop European service.

Likewise, the conference is increasing efforts to promote the flight to the Indian community. Mr. Zapinski said two of the top 10 destinations for travelers on the Pittsburgh-to-Paris flight are in India.

While Pennsylvania and its taxpayers will have to pony up half of the $5 million payment likely due to Delta this year, Gary Tuma, spokesman for Gov. Ed Rendell, said the state is hopeful the flight will prove to be a smart investment.

"We think it is important and desirable from a long-range business standpoint to have the flight in place. If it takes an early investment of taxpayer dollars in a bad economy, we hope it proves to be worthwhile in the long haul," he said.

Kent Landers, a Delta spokesman, said it is "premature" to discuss whether the flight will remain beyond June 2011. "That's a conversation we will have with the Allegheny Conference if that time comes, but we're certainly hopeful that the market sees improvement in the year ahead such that the route can be sustained over time without a subsidy," he said.

Looking for more from the Post-Gazette? Join PG+, our members-only web site. You'll get exclusive sports content, opinion, financial information, discounts from retailers and restaurants, and more. Our introduction to PG+ gives you all the details.