Delta divested its 747s relatively early-on in its history because the airline couldn’t justify its high operating and maintenance costs after encountering lower than expected passenger counts on the routes it served. It subsequently got rid of them in the mid-70s to much agreement within the company. The 747s it inherited after the NWA acquisition where just as quickly divested and sent into mothballs in Arizona. Delta has always been extra frugal when it came to aircraft utilization by…