The Federal Aviation Administration has come down hard against efforts in Washington to raise the federally mandated retirement age for airline pilots.

Some US lawmakers and aerospace groups, including the Regional Airline Association, have been pushing recently for Congress to raise the retirement age as a means of alleviating a pilot shortage.

They want the change written into the FAA’s next spending authorisation.

But the FAA is not on board.

“In the case of possibly implementing an increase in pilot age, we believe it is crucial to provide the agency an opportunity to conduct research and determine mitigations,” FAA administrator Michael Whitaker said in a 5 February letter to the heads of the Senate transportation committee.

Paul Smith in cockpit flight test 737 Max 8

Source: Leo Dejillas/Boeing

A change to the retirement age must only come after “appropriate research, so that the FAA can measure any risk associated with that policy,” adds Whitaker’s letter, addressed to committee chair Maria Cantwell and ranking member Ted Cruz.

US regulations prohibits large airlines from employing pilots age 65 or older. Efforts have been underway to bump that age to 67.

The Regional Airline Association, a group whose members say they have been particularly hurt by an industry-wide pilot shortage, has been a strong supporter of raising the mandated retirement age. US regional airlines have in recent years said too few pilots have forced them to ground hundreds of regional aircraft and to cut flights to smaller communities.

The RAA notes that Canada and other countries have no mandated retirement age for airline pilots.

“Other countries have not conducted research prior to increasing their upper age limit, but in the United States, we have the largest, most-complex system in the world,” Whitaker’s letter says.

Unions like Air Line Pilots Association and Allied Pilots Association have said hiking the retirement age could compromise safety. The unions have also denied that a pilot shortage exists, blaming airline mismanagement and low pay as factors keeping airlines from filling their pilot ranks.

The FAA’s current funding authority is set to expire on 8 March. Lawmakers are now working to extend that funding through new legislation.