The three domestic airlines that operate the Boeing 737 MAX are reportedly devising a publicity campaign to prove that the model is once again safe, The Wall Street Journal reports. The airlines will reportedly conduct demonstration flights with senior company officials on board—and no ticketholders—to reassure the public and pilots that the planes are safe, according to officials familiar with the plan. It is typical for airlines to test aircraft after major modifications, but this time the airlines are planning to fly repeated test trips of the plane. Two 737 MAX flights crashed last year, killing all 346 people onboard. The remaining planes have been grounded since March.

The model has since undergone months of intense analysis and flight testing by the Federal Aviation Administration as well as foreign regulators, especially with regards to the MCAS system believed to be at the center of the crashes. The planes are expected to return to flight in January or February, depending on regulatory approval. “We look forward to supporting our airline customers, their pilots and flight attendants as the MAX returns to commercial service,” a Boeing spokesman said. “Restoring the trust of the traveling public in the safety of the 737 MAX once it’s recertified is our top priority.”