SEATTLE, April 3 — Boeing anti-stall software on a doomed Ethiopian Airlines jet re-engaged as many as four times after the crew initially turned it off due to suspect data from an airflow sensor, two people familiar with the matter said.

It was not immediately clear whether the crew had chosen to re-deploy the system, which pushes the nose of the Boeing 737 MAX downwards, but one person with knowledge of the matter said investigators were studying the possibility that the software had kicked in again without human intervention.

A Boeing spokeswoman declined to comment. Ethiopian investigators were not immediately available for comment. — Reuters