Indication that no drone has ever flown close to an aircraft revealed by the UK Airprox Board - sUAS News - The Business of Drones

https://www.suasnews.com/2019/06/indication-that-no-drone-has-ever-flown-close-to-an-aircraft-revealed-by-the-uk-airprox-board/

The Mysterious And Potentially Revolutionary Celera 500L Aircraft May Fly Soon - The Drive

https://www.thedrive.com/the-war-zone/28409/the-mysterious-and-potentially-revolutionary-celera-500l-aircraft-may-fly-soon