Watch for the surprises in airlifters. China want to exceed from Japan's C-2 and they would do it. Y-15 would be larger thab C-2 ie A400M《C-2《Y-15. More over Y-20B elongated one would reach 100 ton where as Y-40 would be in 125-50 tons category.
Definitely Y-15 would be able to carry 45 tons and mostly between 30-45 tons in its final iterations. Reason for 2 WS-20 engines of Y-15 is engines are available, but WJ-10 are in development. Turboprop version would take more time to mature due to development of 8 blade propellers and WJ-10 turboprop engines.
PLAAF is not going to ignore C-2 competition. It is PLAAF VS JSDAF. It all depends upon engines and subsystem assemblies' progress,
No. Just stop right there.
The wings on the Y-15 are straight, whereas the wings on both the A400M and C-2 are obviously rear-swept.
Straight wing aircrafts excel at low speed flying and maneuvering, which is especially useful for operations from short, austere, hot-and/or-high runways/strips. However, this means that the aircraft won't be flying as fast as non-straight wing aircrafts. This is in contrast with rear-swept wing aircrafts, which excel at higher speeds but have relatively poorer low-speed handling performances.
The PLAAF certainly has emphasized the focus of the Y-15's design on the need to operate from shorter, hot-and/or-high airstrips (namely, in the Xizang Plateau and the SCS), hence the straight wing design we see on the Y-15 today.
This is apart from the fact where turboprop engines have higher fuel efficiencies while operating at lower speeds at relatively lower altitudes, whereas turbofan engines fare worse in similar conditions. This is among the key reasons for turbofan-powered aircrafts to fly faster and higher than turboprop-powered aircrafts.
Also, an airlifter that can still take-off with 4x WJ-6C/G/J/X (or WJ-10) engines will not be comparable to the A400M and C-2, as both of them have different weight categories to begin with.
Sorry to rain in your parade, but the engineers at Shaanxi and Xi'an are very much focused on meeting the needs and demands of the PLAAF as their primary mission, not to engage in a rat race with the C-2 and A400M. Any export orders for the Y-15 would be an added benefit, and not the dominant driver of the Y-15's design choices.