Families of the victims of a UPS cargo jet crash plan to file a wrongful death lawsuit on Wednesday, according to one of the law firms representing the victims.

The UPS MD-11 cargo jet crashed immediately after taking off in Louisville, Kentucky, on November 4, killing 14 people.

Crash investigators with the National Transportation Safety Board found evidence of fatigue cracks in a support structure on the left pylon, which connects to the wing and the plane’s engine, according to the NTSB preliminary report released last month.

The preliminary report “suggests that this plane was old, tired, and well beyond its useful life,” said Bob Clifford, one of the attorneys representing the families.

The plane’s left engine separated from the wing as the plane took off. It crashed into an industrial park next to the airport seconds later, killing the jet’s three crew members and 11 people on the ground.

After the crash, UPS and other operators grounded their fleets of MD-11 cargo jets.

Boeing which acquired the MD-11 program through its 1997 merger with McDonnell Douglas, previously told Reuters that it recommended that UPS and FedEx suspend flight operations of the MD-11 freighter.

(Reporting by Dan Catchpole in Seattle; Editing by Muralikumar Anantharaman and Leslie Adler)