Well, do they really think the PLAAF - with the WS-10C already long mature and the WS-15 around the corner - will consider it as an engine for the J-20?
Even more, I thought the 117S = AL-41F-1S (izdeliye 117S) is the engine used by the T-50/Su-57 ... but what then is 177S?
PLAAF very certainly will consider new, better replacement engines - if only for the AL-31 birds already in service, as WS-10 is not compatible and requires significant changes to the aircraft. There are still hundreds of such aircraft in Chinese service, and they will be in service till 2040s.
PLAAF/PLANAF may not
pick them, but they'll most certainly take them into account, and this is by no means a proposal without merit.
Relationship between countries is also a factor here.
but what is 177S ? which engines ?? i don't know much about Russian numbers.
@gelgoog
Mix between AL-51F and AL-31F with specs very close to the former, but fitting into al-31 nacelle without changes.