The National Transportation Safety Board (NTSB) dropped a doozy on Tuesday: it is reviewing reports of cracks in a wing mount on a UPS freight airplane before its left engine decided to part ways during takeoff from Louisville, Kentucky, in November, leading to a crash that killed 15 people. Because nothing says 'safety first' like a known defect left to simmer.

That revelation kicked off a two-day hearing into the crash of the delivery service’s MD-11, which left all three crew members and 12 people on the ground dead. An additional 23 people on the ground were injured as an auto parts recycling plant ignited after the freighter crashed into it. The plant, presumably, wasn't in the market for engine parts.

Between the crash and the hearing, the board said a cracked part on the doomed jet was flagged in a Boeing 2011 report, which noted there had previously been four such failures on three different airplanes. So, the part had a track record - just not the kind you'd want on your résumé.

The NTSB said its investigation found fatigue cracks in a support structure on the left pylon that connects to the wing and the plane’s engine, known as the bearing race. The agency also said there were a series of reports of cracks in race parts on MD-11 planes in the prior decade. It's almost as if the part was waving a red flag for years.

The hearing is also reviewing the design requirements for those components, along with the Federal Aviation Administration (FAA)’s oversight of the problem over the last two decades. Because why fix something when you can study it for twenty years?

FedEx said it had again started using its fleet of MD-11s after the FAA lifted an order that had barred flying those airplanes after the UPS crash. That came after UPS retired its remaining two dozen MD-11 jets soon after the crash. Better late than never, unless you're on the ground.

Ahead of the hearing, the NTSB released an animated video of the components that failed on 11 November, plus airport surveillance video showing the engine breaking off the jet, which was unable to climb on its remaining two engines and slammed into the ground in a fireball. Spoiler alert: it didn't end well.

The families of several victims who were injured or killed in the crash were present for the hearing in Washington DC. “These families are devastated and certainly deserve answers,” said attorney Bradley Cosgrove, partner at Clifford Law Offices, which is believed to have filed the first wrongful death claim in Kentucky regarding the crash. Cosgrove, who heads up the team of lawyers, pilots and technical experts at the firm, also attended the hearing.

In her opening statement on Tuesday, Jennifer Homey, the NTSB chair, addressed the families of those who were killed in the crash, saying: “Please know: your loved ones are the reason we’re here. We want to find out what happened.” A noble sentiment, though the cracked part might have been a clue.

Furthermore, additional details emerged as the NTSB released more than 2,000 pages of documents related to the plane crash. The ill-fated plane had been pressed into service to substitute another which had a fuel leak, investigators said. And the flight crew who ultimately died had shared good-natured banter with the maintenance team during a second pre-flight inspection about “meeting again” so soon. Dark irony, anyone?

The NTSB was prepared to call several witnesses, including representatives from Boeing, which manufactured the plane. The agency’s final report likely won’t be ready until more than a year after the crash. So, families and the public can enjoy the suspense.

Reuters and the Associated Press contributed reporting.