Proktuka
If I may interject Damien, Robert Rudhall told us at the flypast BB Get-together that Viv did actually fly it, but the handling characteristics were so poor that he was content for it not to be flown again! I wonder if it survived in any other form? It would have made a fascinating piece of aviation heritage in its own right.
Another of those amazing episodes that will become, if it is not already, legendary.