In the now obsolete aircraft that I once worked on category are the DC-8 and B-727. The former airliners were in their waning years operated by UPS (United Parcel Service).
In 1980, UPS opened its first major hub in Louisville, Kentucky, and began acquiring recently retired commercial jet aircraft. These included Douglas DC-8, Boeing 727-100, and Boeing 747-100 units that were converted from passenger aircraft to freighters. Of 556 DC-8 aircraft manufactured from 1958 to 1972, around 200 were still in commercial service in 2002, mostly used as freighters and nearly half (97) were operated by UPS.
I worked with a team of electrical, systems and structural engineers on a multi-faceted project that included instrument panel re-design, and cabin / service bay modifications for the UPS fleet.
On a separate B-727 project, I worked on interior modifications performed on the Chicago Bulls’ NBA team aircraft at Hedrick-Beechcraft/Raytheon in San Antonio. This aircraft was operated by Express One, a Florida-based airline and charter operator.
By 2009, UPS had retired their DC-8 fleet due to aging, ever-increasing operating costs, and strict noise/emissions regulations. The UPS DC-8 final flight landed at Louisville International Airport on May 11, 2009. The first flight of a UPS DC-8 had occurred 21 years prior, on February 1, 1988.