The McDonnell Douglas MD-94X was a planned propfan-powered airliner, intended to begin production in 1994. The aircraft was to seat between 160 and 180 passengers in an unknown seating configuration. An all-new design, it was developed in the late 1980s to compete with the similar Boeing 7J7. Configuration was similar to the MD-80, but advanced technologies such as canard noseplanes, laminar and turbulent boundary layer control, side-stick flight control (via fiber optics), and aluminum-lithium alloy construction were under consideration. Airline interest in the brand-new propfan technology was weak despite claims of up to a 60% reduction in fuel use, and both aircraft were cancelled. Also cancelled was its military counterpart, the McDonnell Douglas P-9D, intended for use by the United States Navy.
Under development at the same time were two propfan variants of the MD-80. The "MD-91X" would have seated 100-110 and entered service in 1991, and the "MD-92X" was to seat 150 and enter service in 1992. Existing DC-9s and MD-80s would also have been eligible for an upgrade to the new propfan powerplants.