The head of the Federal Aviation Administration (FAA) told lawmakers on Tuesday he will use any authority available to him to hold Boeing accountable for any noncompliance that contributed to last month's 737 Max 9 accident during an Alaska Airlines flight.

Why it matters: FAA administrator Michael Whitaker told the House subcommittee on aviation that the agency will not grant Boeing any additional manufacturing expansions for the Max until it's resolved quality control issues.

• Whitaker reiterated the FAA's plan to increase oversight on Boeing after the door plug incident, saying it will have "boots on the ground closely scrutinizing and monitoring production and manufacturing activities."

Catch up fast: On Jan. 5, one of Alaska Airlines' Boeing 737 Max 9 planes lost its exit door plug midflight.

• The near disaster renewed scrutiny on Boeing over malfunctions with the 737 Max 9 jets, which were at the center of two fatal crashes — one in 2018 and another in 2019 — that killed 346 people.
• The door plug incident led to another grounding of Max 9s in U.S. territory. The grounding was later lifted and most of the aircraft have returned to service following an inspection process.
• The inspection process completed by airlines revealed quality control issues with the Max 9s, including loose bolts.

What they're saying: Whitaker said around two dozen FAA inspectors have been sent to Boeing facilities and around a half dozen are at Spirit AeroSystems facilities.

• Whitaker encouraged Boeing workers to use the FAA's confidential hotline to report safety concerns.

The big picture: The Senate confirmed Whitaker as FAA administrator late last year.

• Before Whitaker assumed the role, the agency was without a leader for over a year amid a series of close calls and widespread public frustrations over flight delays and cancellations.
• Whitaker also faced questions Tuesday over recent near misses at several U.S. airports caused by runway incursions, the rate of which fell last year.
• The Flight Safety Foundation in December called incursions "the most persistent threats to aviation safety" and warned that the likelihood of incursions is expected to increase as air traffic grows.
• To address the near misses, Whitaker said the FAA has started using new data analytics and runway designs, as well as more training for air traffic controllers.

What's next: The National Transportation Safety Board is expected to release its preliminary report on the Alaska Airlines incident soon.

Go deeper: Boeing reworking 50 undelivered 737 MAX jets over fuselage issue