L-15 and Yak-130 – The connection

The Yak-130 and L-15, i hope this clears it up

The only possible help the Yak company gave to china was probaly the layout of the wings and maybe the airtake since they were asked to consult. But apart from that the original L-15 concepts were pretty much similar since both parties were designing similar aircraft. Its a chinese plane with some Yak help. Below is a quote itself from the Yak design bureau about their own involvment

Another “relative” of the Yak-130 (a remote one, frankly) is the L-15 supersonic trainer China develops with Yakovlev’s assistance. Says Yakovlev’s Director General Oleg Demchenko: “Our full-scale cooperation with the Chinese aircraft industry dates back to 2000 when the AVIC II corporation, based on Yakovlev’s advances in Yak-130 development, invited us to join the L-15 supersonic trainer development programme. The L-15 developer is the Hongdu company in the city of Nanchang, a specialist in developing such planes. Its K-8 trainer is in production and sells well enough on the global market. The L-15 is being developed to meet the requirements of the People’s Liberation Army (PLA). Yakovlev’s role is consulting, which can be called scientific and technical support of the aircraft development programme. We are participating at the preliminary design stage, while the Chinese side is fully in charge of working out the design documentation and making the aircraft. This is a Chinese plane. The Chinese designers just correlate their technical solutions with the opinion of ours.”

Yakovlew design bureau