Boeing 737 Max...per the FAA
(too soon?)
DC-10s killed way more people in the 70's, it took them longer to ground them and address issues, and some pilots gave them the nickname "death cruisers"...but they still went on to have a pretty successful life once they fixed what they needed to. The A320 had some issues too and there were crashes before it became a popular plane. Fly-by-wire was a radical concept in 1988. That being said, I'm glad they are looking into what the issue is with the MAX, and I'm certain it'll be a very airworthy craft.