U.S. officials gave an update to a congressional committee on their investigation into a jetliner that suffered a midair blowout earlier this month, informing the representatives that they had inspected 40 Boeing planes identical to the one that lost a panel of its fuselage midflight on January 5.

According to the Associated Press, Jennifer Homendy, the chair of the National Transportation Safety Board (NTSB), and FAA administrator Mike Whitaker briefed members of the Senate Commerce Committee on their findings for about two hours January 17. Both officials said that the investigations into the accident and Boeing are currently in their early stages.

Senator Jerry Moran (R-KS) said that the officials did not mention anything about any penalties that would be enforced on Boeing for the blowout. Moran also said that Whitaker indicated the FAA is looking into “the challenges that Boeing has faced over a longer period of time, of which this incident, this potential disaster, was only one component.”

The Federal Aviation Administration (FAA) said that it will continue to review the information from the inspections of Boeing 737 MAX 9 jets and develop a maintenance process for those aircraft before allowing the planes to once again carry passengers.

According to NTSB investigators, a door plug on Alaska Airlines flight 1282 somehow moved off a set of stops designed to keep it attached to the plane, causing a dangerous blowout to occur at around 16,000 feet on January 5. All 177 people aboard the flight at the time of the blowout survived the incident.