WASHINGTON (Reuters) – Republican Senator Chuck Grassley said Friday he is launching a new congressional oversight inquiry into the Federal Aviation Administration and Boeing after a January mid-air emergency involving a 737 MAX 9.

The probe is the latest in a series of investigations by lawmakers since the incident. Grassley, who first probed Boeing safety actions in the 1990s, said Boeing and the FAA “must explain how this happened and what is being done to ensure that it does not place the lives of Americans at risk again.” He asked the FAA and Boeing to answer a total of 38 questions “requesting records of safety procedures, regulatory requirements, corrective actions (and) whistleblower protections.”

(Reporting by David Shepardson)