China's transport, tanker & heavy lift aircraft


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And also I can't add up all the YY-20A that has been built so far. With the last 8 seen so far in a january satellite picture, what is the total visually confirmed YY-20A? 23?


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So is there in fact no meaningful distinction on "tanker" vs "cargo" Y-20Bs, they're all interchangeable?

That is the understanding.
However as I wrote Y-20B as a tanker lacks the centreline fuselage refuelling position that YY-20A has.

Have there been any recent updates on the progress of the type?

I don't know, what is an update defined as?
We are basically just waiting for pictures of the type in service, which predictably will be long delayed after it actually occurs


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He wrote "MTT" which probably means "MRTT" which is an aircraft that can operate as both a tanker or a transport, and that is what we expect all standard Y-20Bs to be able to do by virtue of wing pods (no Centreline fuselage pod)

That said I'm also really not a big fan of these oversimplified graphs he makes.
The sad fact is that we live in a world where the oversimplified graphs from some twitter user is more accuracy and informative than virtually all think tank and government reports.


Refueling J-20s.




Looks like 3 is a common denominator in this picture.

21 Y21 divided by 3 = 7
6 greenish yellow Y20 at bottom left of enlarged picture divide by 3 = 6
6 dark color Y20 at the left bottom of enlarged picture divide by 3 = 2
another 3 dark color Y20 at the top left of the enlarge picture divide by 3 = 1

May be, just may be there is an equation like

X * 3 * P = AP

3 is a constant

X = # of production line
P = production turn-over cycle per year

AP = Annual Production number.

Don't take this seriously, just something suddently flashed through my mind. Other satellite images may showed otherwise.


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Due to the lower resolution of the latest satellite photograph of Xi'an AC, it should be noted that rough guess-timates is what I can only do at best.

Firstly, for the Y-20s with grey paint - Due to them having nearly similar color to their respective shadows on the ground, it is very difficult to ascertain the engine's dimensions from guess-timations. So we'll leave them at that.

That leaves the Y-20s with green primer, as their color sharply contrasts with their respective shadows on the ground.


While I don't have first-hand information on the exact dimensions of the WS-18 and WS-20 (including their engine cowlings) - I do believe that resorting to roughly comparing the diameter of the engine cowlings of the WS-18 and WS-20 versus the fuselage diameter of the Y-20 should work somewhat.


Hence, with the prior setting in place - It can be said (both from observations of real-life photographs and the above CG illustration by @Astrosiren on Weibo) that the WS-18's diameter is roughly one-third to one-fourth that of the Y-20, whereas the WS-20's diameter is roughly one-half that of the Y-20.

Also, it should be noted that the engine cowling of the WS-18 does extend slightly beneath the leading edge of the wings of Y-20/A, whereas the engine cowling of WS-20s ends roughly almost right at the leading edge of the wings of the Y-20B. Again, clarification - Due to the (understandably slightly slanted) angle of the satellite taking the above photograph relative to the individual Y-20s on the ground, such method can still result in some degree of uncertainties with such methodology.

Therefore, from personal observation and guess-timations of the photograph - I believe that there are most likely at least some number of Y-20s in green primer that are of the Y-20B variant (i.e. with WS-20 engines) at Xi'an AC as late as early this month.

In the meantime, there may be two Y-20/As in green primer on the right side of the 1st photograph with WS-18 engines, though I'm not so sure whether that's the actual case.
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