The YPX is to seat between 100-150 passengers, and would thus be competitive with the smaller Boeing 737 and Airbus A320 family jets on short haul routes. The engine choice has not been made. Entry into service was expected to be somewhere around 2015. However, as of 2015, no prototype was built. Kawasaki hopes offer up to 15% cash operating savings over the Boeing 737-700.
According to specifications issued in 2007, the base model YPX-11 would seat 113 passengers in a two-class arrangement. The YPX-10 would seat 93 in two classes while the YPX-12 would accommodate 137, implying about 150 in an all-economy arrangement. Standard range for all three body lengths would be 4,260 km (2,300 nautical miles) but the YPX-10 and YPX-11 would have extended-range sub-variants flying as far as 5,930 km (3,200 nautical miles).
YPX would have a five-abreast economy cabin and an elliptical cross-section - that is, with a smoothly varying radius, rather than the old double-bubble based on two distinct radii. Economy seats would be 46 cm (18 in) wide; the aisle, 51 cm (20 in).