[stangles1]

The comparison to the C-17 rather than the C-5 seems rather deliberate to me (along with using lbs instead of tons for the unit). It's more sensational if a future Chinese military cargo plane "beats" a US cargo plane in cargo capacity by XXX,000 of anything.

[to3m]

Any time they don't translate between units, or mix different types together, I assume the writer is not only functionally innumerate, but also just repeating what somebody else has told them to say...

Also note that (according to Wikipedia) the capacity is 250,000kg - so 275 tons, or 551,155 lbs.

The C-17's cargo capacity (again, from Wikipedia) is 77,500kg - so 85 tons, or 170,858lbs. That looks a lot more like a difference of 380,000lbs than 300,000lbs to me, which, with some journalistic licence, could surely become "almost 400,000lbs more". You may well be correct about the sensationalism aspect, and here they are leaving some of that on the table.

So I don't really know what's going on. Like I said, functionally innumerate... (Though of course, calculation error at this end is always a possibility! But nobody's paying me to do this, so I'm going to go with my gut here.)