WASHINGTON, Jan 31 (Reuters) - The Federal Aviation Administration said on Wednesday that its previously announced audit of Boeing 737 MAX manufacturing will look at all elements of production at Boeing and fuselage production at Spirit AeroSystems'.

The FAA said a team of two dozen aviation safety inspectors will conduct the audit at the Boeing 737 facility in Renton, Washington, and at Spirit in Wichita, Kansas. The audit will also examine how Boeing transfers unfinished work from suppliers to its production lines.

The FAA announced the audit on Jan. 13 after the agency grounded 171 MAX 9 planes due to a mid-air cabin panel blowout on a new Alaska Airlines MAX 9. The FAA last week allowed the planes to fly again.

The FAA said it is conducting enhanced oversight of Boeing and "will regularly assess trends, corrective actions and the effects of any changes to the quality system." The FAA did not say how long the greater scrutiny would last.

FAA Administrator Mike Whitaker told Reuters this month the Boeing production audit would begin with the 737 MAX and extend to other planes as warranted by data.

Whitaker said the FAA audit "is to look at the system, look at how the inspections are done, where they're done, how the interaction is with the suppliers, how the handoff happens, just the whole process to really understand how it works and where the faults might be."

Spirit AeroSystems, which did not immediately comment Wednesday, said previously it is "committed to supporting the FAA’s audit of production and manufacturing processes."

Boeing CEO Dave Calhoun said Wednesday the planemaker is "taking immediate and comprehensive action to strengthen quality at Boeing and within our supply chain."

The National Transportation Safety Board is looking at whether the bolts attaching the cabin panel in the Jan. 5 incident were missing. The FAA has opened a separate formal investigation into the MAX 9. (Reporting by David Shepardson; Editing by Leslie Adler and Cynthia Osterman)