The Federal Aviation Administration will step up inspections of aircraft manufacturer Boeing, the agency's top official told lawmakers Tuesday. 

FAA chief Mike Whitaker's appearance before a House panel comes a month after a door panel blew off of a Boeing 737 Max 9 jet while flying, raising concerns about Boeing's manufacturing process and the agency's oversight of the plane maker.

"We will have more boots on the ground closely scrutinizing and monitoring production and manufacturing activities," Whitaker told the aviation subcommittee of the House Transportation and Infrastructure Committee. "Boeing employees are encouraged to use our hotline to report any safety concerns." 

The FAA grounded all U.S.-based Max 9 jets after the January 5 incident that occurred on an Alaska Airlines flight, just minutes after the aircraft took off from Portland, Oregon. The agency late last month cleared the aircraft for flight after inspection.

The FAA anticipates having enough information from a probe launched after the near-catastrophic accident to make recommendations as soon as later this month, the agency said on Monday. 

The agency currently has about two dozen inspectors at Boeing and about half a dozen at Boeing supplier Spirit AeroSystems, Whitaker, a former airline executive who took the helm of the FAA in October, told lawmakers. 

The FAA has long relied on aircraft manufacturers to perform some safety-related work on their planes. That saves money for the government, and in theory taps the expertise of industry employees. But that approach was criticized after two deadly crashes involving Boeing Max 8 planes in 2018 and 2019.

"In order to have a truly safe system, it seems to me that we can't rely on the manufacturers themselves to be their own watchdogs," Rep. Colin Allred, D,-Texas, said during Tuesday's hearing.

Raising the retirement age for pilots

Separately, the issue of raising the retirement age for pilots came up at the hearing. Last year, the House voted to increase the retirement age to 67 from 65 for pilots as part of a broader bill covering FAA operations. A Senate committee is scheduled to take up a version of the measure Thursday.

At Tuesday's hearing, Whitaker said the FAA said the agency wants to first study the potential safety risks of raising the mandatory retirement age. 

"If you're going to change it we'd like to have some data around that," Whitaker said.

—The Associated Press contributed to this report.

In:
• Federal Aviation Administration
• Boeing

Kate Gibson

Kate Gibson is a reporter for CBS MoneyWatch in New York.