UPS has decided to ground its MD-11 aircraft fleet 'out of an abundance of caution' following a deadly crash at its global aviation hub in Louisville, Kentucky. The decision, announced late Friday, comes after a tragic incident earlier in the week that resulted in the loss of 14 lives, including three pilots.

The MD-11s account for approximately 9% of UPS's airline fleet. This precautionary action was taken on the advice of the aircraft manufacturer, emphasizing the company's commitment to safety for its employees and the communities it serves.

While the grounding is termed temporary, the timeline for returning the planes to service remains unclear. Boeing, which acquired McDonnell Douglas in 1997, has yet to provide a specific reason for the recommendation to ground the aircraft.

The crash occurred as the plane was nearly airborne, with alarming indications of failure occurring seconds before takeoff. Preliminary reports suggested that the pilots heard a bell sound in the cockpit shortly after initiating takeoff thrust, signifying a critical error. Despite their efforts to stabilize the aircraft, it was engulfed in flames and crashed dramatically just off the runway.

National Transportation Safety Board representatives indicated that investigation into the cause of the crash is ongoing, and the cockpit voice recorder will help shed light on the sequence of events that led to this tragedy. The findings are expected to take several months as they analyze collected data, including multiple angles captured by surveillance and bystanders.

This tragic incident has affected operations at UPS Worldport, the company’s largest hub, which normally handles hundreds of flights and processes a significant volume of packages daily. Operations resumed shortly after the crash, focusing on Next Day Air sorties, according to a spokesperson.