Boeing's head of quality for commercial airplanes, Elizabeth Lund, who has spearheaded the planemaker's improvement plans, will retire in December, the company said on Monday.

A 33-year veteran of Boeing, Lund had been named in February to the new position of senior vice president of quality for its commercial planes, after the crisis sparked by the Jan. 5 mid-air panel blowout of a new Alaska Airlines 737 MAX 9.

In June, the National Transportation Safety Board said Boeing violated investigation rules when Lund provided non-public information to media and speculated about possible causes of the blowout. The agency barred Boeing from receiving information produced during its probe.

Federal Aviation Administration chief Mike Whitaker took the unprecedented step in January of preventing Boeing from expanding 737 MAX production until he is satisfied it has made significant quality improvements.

Boeing has been implementing a quality plan it submitted to the FAA in May as it seeks approval to boost 737 MAX production.

Lund will be replaced by Doug Ackerman, who has served as vice president of Supply Chain and Fabrication Quality and has been involved in the quality plan.

Last month, the FAA said it would open a new safety review into Boeing, looking at issues like risk-assessment quality, resource allocation and adherence to regulatory requirements. The review is expected to take three months.

Also in October, the Transportation Department's Office of Inspector General criticized FAA oversight of Boeing, saying the agency lacked an effective system to oversee the planemaker's individual manufacturing facilities.

An FAA audit of Boeing completed in February found 97 incidents of noncompliance, spanning "issues in Boeing’s manufacturing process control, parts handling and storage, and product control."

Whitaker said recently that Boeing's improvements in safety culture might take three to five years to implement. In June, he acknowledged that the agency was "too hands-off" in its oversight of Boeing prior to January.

Whitaker spoke to Boeing CEO Kelly Ortberg last week on the planemaker's plans to resume 737 MAX production following a 53-day strike.

Lund said at an NTSB hearing in August that the planemaker was working on design changes it hoped to implement within the year and then to retrofit across the fleet to prevent a future incident.