The ongoing debate over the nation's "Open Skies" agreements is heating up, and taking a decidedly political turn.
The U.S. has over 100 of these agreements with other countries, meant to remove government interference in the decisions airlines make about their routes, capacity, pricing and other commercial variables.
The U.S. State Department has hailed the Open Skies policy as having "vastly expanded international passenger and cargo flights to and from the United States, promoting increased travel and trade, enhancing productivity, and spurring high-quality job opportunities and economic growth."
But on Wednesday, more than 250 members of the House of Representatives sent a letter to Secretary of State John Kerry and Transportation Secretary Anthony Foxx, calling on the Obama administration to investigate the governments of Qatar and the United Arab Emirates (UAE).
According to that letter, the two Gulf nations have directed more than $40 billion in "concealed subsidies and other unfair benefits" to state-owned airlines like Qatar Airways, Etihad Airways and Emirates Airlines.
"We are concerned that Qatar and the UAE are using these subsidies and other unfair practices to distort the market in favor of their state-owned airlines, contrary to U.S. Open Skies policy," the letter continued.
The bipartisan group of Representatives also said the subsidized Gulf carriers are undercutting hundreds of U.S. jobs.
But the lawmakers' claims are being disputed by groups like the U.S. Travel Association (USTA), which points out that four U.S. airlines now control 85 percent of the nation's passenger traffic, due to what it calls the airline industry's "radical consolidation of the last several years."
The USTA also contends that the big U.S. airlines are trying to eliminate overseas competition and maintain a tighter hold on the nation's air routes.
In an opinion piece published earlier this week in the Chicago Tribune, USTA president and CEO Roger Dow said airfares on Open Skies routes are about one-third lower than regulated air routes.
"Last year, 74 million international travelers visited the U.S. and spent $180 billion on travel goods and services, directly supporting more than 1 million U.S. jobs," he added. "Those numbers will fall if we limit flights here but rise if we expand them."
Dow also warned that if the big U.S. airlines end up limiting Open Skies, "it will destroy the very foundation of Open Skies around the world. Then we'd be back to an era of regulated aviation, higher fares and fewer consumer choices."