No oil was visible in the gauge on the right engine’s oil reservoir after a February Delta Air Lines flight filled with smoke during takeoff at Atlanta’s Hartsfield Jackson International Airport, a preliminary report from the National Transportation Safety Board said Wednesday.

That was the case this week on a Delta Air Lines flight I took from Grand Rapids to Minneapolis on my way to Mountain View, California, for Google I/O. Because of weather over parts of the Midwest, a thing that regularly disrupts travel in these parts, our flight was delayed at the gate for an hour or so.

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