Just been reading throught this fascinating thread and a memory I can contribute - OT as it involved fixed wing but relevant as one of the de Ferranti's was flying it - was a trip I had from Manchester Barton in EI-ARN, a Wren 460 which was a modified STOL version of the Cessna 182. I was young at the time but remember the CAA didn't like the Wren so it was registered in Ireland. I also remember the thing climbed like a homesick angel!