Delivered new to Fluor Corp as N401M in Dec 1975. To N144ST in Apr 1988. To N7766Z in Sep 1990. Converted to a II-SP in Apr 1996. To N900ES in Jul 1996. To N540EA on 19 May 1997. WFU. Cancelled from the US register on 11 May 2016. Still current in 2024.