Delta Airlines flight DL-159 made an emergency landing in Detroit, Michigan, on May 20th.
The Boeing 747-400 plane took off for Seoul, South Korea, but had to return shortly afterwards due to indication of an open panel door.
The plane landed back safely. All 375 passengers aboard remained unharmed.

American Airlines flight AA-1157 made an emergency landing at Miami International Airport, Florida, on December 28th.
Thai Lion Air flight SL-539 had to divert and make an emergency landing at Chiang Mai International Airport, Chiang Mai, Thailand, on April 10th.