Smoke in the cabin led to an emergency landing of a Delta flight in February. Only later did officials realize there was little to no oil in the aircraft's right engine. That reveal, coming in a National Transportation Safety Board preliminary report released Wednesday,

A Delta flight that made an emergency landing in Atlanta in February had no visible oil in its right engine, the National Transportation Safety Board announced on Wednesday.

After a Delta flight made an emergency landing in Atlanta in February, a maintenance crew found there was barely any or possibly "no oil visible" in the aircraft's right engine.