Boeing is grounding dozens of 737 MAX aircraft.
The aircraft manufacturer is doing this because of an electronic defect that must be remedied.
The aircraft were only released for use a few months ago, after having been grounded for months due to two deadly disasters in a short period of time.
Boeing has identified the potential problem with some MAX aircraft and has warned 16 customers operating such aircraft not to use them.
According to the US aviation authority FAA, this is a production problem that affects a specific group of aircraft rather than the entire fleet.
The 737 MAX has been grounded worldwide since spring 2019 after two accidents within months.
In both cases, a safety system was found to push the nose of the aircraft down repeatedly, even when it was not necessary.
The crashes in Indonesia and Ethiopia killed 346 people.
The problem is now not related to the malheur of the time, Boeing reports.
Nevertheless, the problems are very likely to put another dent in confidence in the aircraft manufacturer.