In 1950 NW2501 went down in Lake Michigan with 55 passengers and three crew. The airplane was on radar, only 18 miles from the shoreline. To this day, it has never been found. Clive Cussler, the author, funds an annual search for the missing airplane in the lake with underwater gear. No CVR/FDR, No pinger.
So maybe we will never find MH370.....