The federal government is allowing airlines to continue to run reduced flight schedules to major airports serving New York City and Washington in hopes of curbing flight cancellations and reducing the burden on short-staffed air traffic controllers.

The Federal Aviation Administration is extending the relaxed requirements it first announced last March that permitted airlines to scale back summer schedules without forfeiting competitive "slots" into New York's LaGuardia, JFK, and Newark airports as well as Reagan National Airport outside D.C.

The FAA says the slot waivers — initially set to expire on September 16 — have been extended another six weeks until October 28. The new extension follows pleas by United Airlines and the airline industry's top lobby, Airlines for America.

In a statement, the FAA says it "continues to expect that airlines will operate larger aircraft to transport more passengers and make sure passengers are fully informed about any possible disruptions."

Still at issue are air traffic controller shortages at New York Terminal Radar Approach Control. In March, the FAA said the facility was staffed at 54% of its target level.

In a Wednesday filing, the FAA said it "continues to monitor performance" at the facility and "assess options for addressing the staffing shortages," but "FAA efforts will not be completed in time to address the near-term anticipated operational impacts in the remainder of the summer 2023 scheduling season."

The FAA insists summer schedule relief has worked, causing cancellations at Newark, JFK, and LaGuardia to fall 40% between May 15 and June 30.

CNN has reached out to United Airlines and Airlines for America for comment.

Airline staffing shortages

Shortages extend beyond air traffic controllers, too.

Despite $54 billion of taxpayer funds funneled into airlines to keep them alive during the pandemic, most airlines greatly reduced staff during the first year of the pandemic when air travel, and fares, plunged. They were not allowed to involuntarily layoff staff but they did offer buyouts and early retirement packages. Many also permanently grounded older, less efficient aircraft. Rehiring staff has taken longer than planned.

The result has been that domestic US airline capacity, as measured by the number of available seats adjusted for miles flown, is still down 10% in the current quarter compared to the second quarter of 2019, ahead of the pandemic, according to data from Cirium, an aviation analytics firm.

And when problems occur, finding seats for passengers whose flights have been canceled becomes a problem, particularly at busy travel periods.