It’s a flyer’s worst fear: Looking out the window of a plane and seeing something wrong with one of its wings.

Now imagine seeing an engine cover come off — in midair — as you’re peering out said window.

That’s exactly what happened on Tuesday during United Airlines Flight 1175 from San Francisco to Honolulu. The terrifying scene was captured by passengers, who posted photos and videos on social media.

Click the link below for the full story and video!

United 777 loses engine cover