Passengers on a Jin Air flight bound for South Korea discovered that their plane door was partially opened about 40 minutes into their flight — while the more than 160 passengers were 10,000 feet in the air, CNN reports. The crew was forced to make an emergency landing in the Philippines after they noticed the gap by the weird noise it was making. 

Passengers also reported feeling nausea during the flight. This is a natural response, of course, to realizing the plane door is open.

Sources: CNN