Kawasaki YPX

The Kawasaki YPX was a twinjet airliner proposed by the Japanese aircraft manufacturer Kawasaki Aerospace Company. It was heavily based on the Kawasaki P-1 maritime patrol aircraft that was developed for the Japan Maritime Self-Defense Force.

As envisioned, the YPX was to have seated between 93 and 150 passengers, and would have contested market share with existing regional airliners from both Bombardier Aviation and Embraer, as well as the smaller Boeing 737 and Airbus A320 family jetliners on short haul routes. Work on the YPX was performed in association with the Japan Aircraft Development Corporation (JADC) and, if the project had received authorisation to proceed, have likely involved various other firms beyond Kawasaki, including Fuji Heavy Industries, Mitsubishi Heavy Industries, and possibly even the Taiwanese aircraft producer Aerospace Industrial Development Corporation.

Market research determined that many prospective customers sought operational savings over incumbent competitors of up to 30 percent; Kawasaki had internally aimed to achieve a 15 percent operating cost reduction in comparison to the Boeing 737-700. It was recognised that substantial design work, including the adoption of a twin-engine configuration instead of the P-1's quad-engine arrangement, would have been necessary to produce a viable airliner. Development of the YPX was paused during the early 2010s and there has been no progress as of 2024. No known prototype has been built.