The Eagle was a lightweight to rig compared to Sigma; Nick Goodhart designed a naval sheerleg hoist arrangement which fitted onto the trailer, I think they would have needed 2 retrieve vehicles for the crew.
Dr Wortmann, who supplied the wing section, visited UK to look at it. Invited for an opinion, he replied "If I wanted a Swiss watch, I would not employ a blacksmith to make it".
It was constructed by Slingsby's, who were also building the T53 at Kirbymoorside.