https://www.janes.com/defence-news/news-detail/japan-uk-discuss-partnership-on-fighter-jet-engines
The governments of Japan and the United Kingdom are discussing a potential joint programme to develop aero-engine technologies that will power Japan's next-generation F-X fighter aircraft, officials have confirmed to Janes.

ジェーンズは共同のエンジン技術開発joint programme to develop aero-engine technologiesという表現だったな
可変サイクルの共同研究、発電機等の一部構成品共通化と幅広く取れるが