NTSB to Issue Recommendations on 737 Max Certification

U.S. air crash investigators, who are assisting in probes of two fatal crashes of Boeing Co.’s grounded 737 Max, plan to issue recommendations within 60 days on how the plane was designed and certified.

The board will issue a recommendation package on “design certification issues,” National Transportation Safety Board Chairman Robert Sumwalt said Wednesday at a Senate Commerce Committee hearing.

Most of NTSB’s recommendations come in domestic accidents, but it has made sweeping requests in foreign investigations, including after the disappearance of Malaysia Airlines Flight 370 in the Indian Ocean in 2014.

Details of what the safety board will call for in the package weren’t revealed.

“We will let the facts drive us, but I am told that our staff is working on a recommendation package that I would suspect we would have out in the next 60 days regarding design certification issues,” Sumwalt said while testifying at a hearing on his confirmation for another term as chairman.

The NTSB is assisting investigations into crashes of a Lion Air jet in October off the coast of Indonesia and a Ethiopian Airlines plane near Addis Ababa in March. In both cases, a system designed to improve safety on the plane malfunctioned and repeatedly drove down the nose of the jets until pilots lost control.

China and some other nations grounded the Max family within a day of the March 10 crash. The U.S. waited until March 13 to halt flights on the planes.

Multiple U.S. government agencies are examining how the plane was designed with the system, known as Maneuvering Characteristics Augmentation System, and how it was certified by the Federal Aviation Administration. The U.S. Justice Department is conducting a criminal investigation of the issue as well.

A policy of designating approved employees of the planemaker to participate in the certification process has drawn criticism.

MCAS was designed to make the plane feel like the previous generation of 737s after the Max got larger engines. In some circumstances, it pushes the nose down so pilots will feel pressure on their control columns. In the accidents, a sensor that was driving MCAS malfunctioned and was sending erroneous signals that triggered repeated attempts to automatically dive.

Boeing is redesigning the system so that it won’t activate continually and is adding inputs from a second sensor so that malfunctions are less likely.

The NTSB, which has no regulatory authority, relies instead on making recommendations to other agencies and companies during an investigation. They are non-binding and can seek a variety of reforms or redesigns.