A Russian-made passenger plane has encountered delays days after an emergency landing ended in a plane fire that resulted in the deaths of 41 people in Moscow.

Questions resurfaced about the Sukhoi Superjet 100’s safety after one of the planes crash-landed shortly after takeoff at Sheremetyevo Airport on Sunday, killing 40 passengers and one flight attendant. An investigation is considering several causes of the disaster, including a defect on the plane.