Mass production means a large number has produced.
For example, at least above 100 pieces.
Well... maybe you should learn abit about business before coming in and post your own opinion. WS-10A had been certified for mass production, which MEAN it is ready for mass production. The only reason you don't see that huge amount of them is because there is no order yet.
Why the hell do you want to build 100 engines when there is no body to fit to? As spare?
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