In a cautious move, UPS and FedEx announced on Friday that they are temporarily grounding their fleets of McDonnell Douglas MD-11 aircraft. This decision follows a directive from the Federal Aviation Administration issued the next day, which mandates that these planes remain grounded until they are thoroughly inspected and any potential issues are resolved.

The urgency of these actions stems from a recent incident in Louisville, where an MD-11’s left engine detached during takeoff, leading to a catastrophic crash.

Dramatic video footage captured the moment the aircraft plummeted into nearby businesses, resulting in a fiery explosion.

Investigators are now examining multiple sources of video evidence, including footage from smartphones, vehicles, and security cameras, providing them with a comprehensive view of the event from various perspectives.

Flight records indicate that the ill-fated UPS MD-11 had been grounded for maintenance in San Antonio for over a month, up until mid-October.

However, the specific maintenance work performed during that period remains unclear at this time.

The UPS package handling facility in Louisville is the company’s largest.

The hub employs more than 20,000 people in the region, handles 300 flights daily and sorts more than 400,000 packages an hour.

UPS Worldport operations resumed on Wednesday night with its Next Day Air, or night sort, operation, spokesperson Jim Mayer said.