Base on this document, they developed a significant type Air-to-surface missile base on the technology of M-20. So I think they use the M-20 as second stage of the CH-AS-X-13.
https://thediplomat.com/2018/04/revealed-chinas-nuclear-capable-air-launched-ballistic-missile/
China is developing and has been flight-testing a nuclear-capable air-launched ballistic missile (ALBM) along with a new long-range strategic bomber to deliver it, The Diplomat has learned...
https://thediplomat.com/2018/04/revealed-chinas-nuclear-capable-air-launched-ballistic-missile/
China is developing and has been flight-testing a nuclear-capable air-launched ballistic missile (ALBM) along with a new long-range strategic bomber to deliver it, The Diplomat has learned...
I believe this should be posted in another thread:
https://defence.pk/pdf/threads/china-space-militaryrecon-satcom-navi-asat-bmd-orbital-vehicle-slv-etc.84216/
Seriously? In my memory, the document about the woman scientist had been posted in the thread. And fzgfzy had said the railgun even will not be installed on the Early variant of 055B.