The
            Boeing 707, although not the first jet airliner, was the
            right aircraft at the right time and truly opened the era of jet air
            travel.
            Based on the KC-135, the
            707 had a slightly wider fuselage (148 in v. 144 in) and was in
            development at the same time as the military tanker.  
            The first production 707 flew with Pan American in
            1958.  The last commercial 707 was sold in 1982.
            The U.S. Air Force purchased 707s as VIP
            Transports designating them the VC-137.  Several VC-137s served
            as "Air Force One" until replaced by the Boeing
            VC-25 (747).