A Boeing 737 Max 8 plane being flown by Southwest Airlines made an emergency landing in Orlando on Tuesday afternoon after reporting an engine problem shortly after taking off, the airline said.

The plane — the same type that crashed in Ethiopia earlier this month and in Indonesia in October — had a two-person flight crew but no passengers on board. It was being flown to California for “short-term storage” after the United States ordered the grounding of all 737 Max planes following the two crashes, which killed hundreds of people.

The engine problem was unrelated to an automatic system on the plane designed to help it avoid stalling, which is being investigated in connection with the two crashes.

“The crew followed protocol and safely landed back at the airport,” Southwest said.

The Max 737, Boeing’s best-selling plane, has come under intense scrutiny after the two deadly crashes.