The WS-21 engine and the RD-93MA engine are like cousins with the same bloodline.
Russia's development path:RD-33......RD-93......RD-93MA
China's development path: RD-33......WS-13......WS-21
Yes. They share a common ancestor.
A recently unveiled scale model of the WS-21 engine reveals changes to its internal structure.
Comparing the two engines' performance figures is meaningless. Generally speaking, the two engines' performance figures are comparable. The difference lies in the WS-21's greater technological transfer from next-generation engines (derived from the WS-19/WS-15).
But one thing is certain: the WS-21 engine is significantly more expensive than the RD-93.
The price of the RD-93 engine has been fluctuating due to international factors. Its actual transaction price has fluctuated between $2.5 million and $5 million.
Pakistan previously purchased a WS-21 engine from China. The price is 100 million RMB, or approximately $14-16 million USD. Since this order is for a single engine and its intended purpose is unclear, we cannot estimate the price of the WS-21 engine in a bulk order. However, this would still represent a significant price difference. (The WS-21 engine uses too many expensive specialty materials and next-generation engine technologies, which has caused its manufacturing costs to soar)
Thus, if subsequent versions of the JF-17 adopt the WS-21 engine, the final price of the entire fighter jet would approach that of the J-10CE, making it completely uncompetitive in the market.