A group of outside experts appointed by the Federal Aviation Administration called on Wednesday for “urgent action” to address safety risks in the nation’s aviation system, highlighting issues like staffing shortages among air traffic controllers and outdated technology.
The F.A.A. announced the formation of the group, the National Airspace System Safety Review Team, in April after a string of close calls at airports across the country, and the panel issued a 52-page report on Wednesday laying out its findings.
In addition to calling for the F.A.A. to address the shortage of air traffic controllers and improve its aging technology, the report also recommended changes in how the agency is funded, such as more broadly shielding it from government shutdowns.
“The current erosion in the margin of safety in the N.A.S. caused by the confluence of these challenges is rendering the current level of safety unsustainable,” the report said, referring to what is known as the National Airspace System.
The group of experts was led by Michael P. Huerta, who served as F.A.A. administrator under Presidents Barack Obama and Donald J. Trump. It also included other former federal officials and former union leaders.
“There are no easy short-term fixes to address many of these challenges,” Mr. Huerta told reporters on Wednesday. “Addressing risk in the N.A.S. requires the F.A.A., the administration, Congress and others across industry to work together collaboratively.”
New York Times investigations published in August and in October revealed how the nation’s vaunted aviation safety system is under mounting stress. The Times found that close calls involving commercial airlines had been happening, on average, multiple times a week.
A dire shortage of air traffic controllers — The Times found that 99 percent of the country’s air traffic control facilities were understaffed — has been one major factor.
The report released on Wednesday also warned about the risks posed by aging technology. In January, an F.A.A. system outage caused flights to be grounded nationwide and led to a wave of delays and cancellations for travelers.
“The age and condition of F.A.A. facilities and equipment are elevating system risk to unsustainable levels, even before considering losses in efficiency from outdated technology,” the report said.
The agency has said that it has taken steps to reduce the risk of close calls at airports, such as by providing funding to reconfigure taxiways and improve runway lighting.
“The F.A.A. welcomes the independent Safety Review Team’s report, and we will thoroughly review the recommendations,” the agency’s new administrator, Michael G. Whitaker, whom the Senate confirmed last month, said in a statement. “We appreciate the team’s time and expertise to help us pursue our goal of zero serious close calls.”
The near misses have also caught the attention of Congress. A Senate subcommittee held a hearing on the topic last week, and among the witnesses was Jennifer L. Homendy, the chairwoman of the National Transportation Safety Board, which is investigating a number of close-call incidents.
“While these events are incredibly rare, our safety system is showing clear signs of strain that we cannot ignore,” Ms. Homendy said.