"I cannot remember the aircraft type that either Alex Henshaw or Eric Brown said that the worst the had ever flown. All I do remember was that is was inflatable."
That's proably the M L Utility
https://www.flightglobal.com/pdfarch...0-%200745.html aka "Dumbo the Durex Delta".
I doubt whether Alex Henshaw would have flown it; Winkle might have.
I rather like the quote attributed to a U S Navy pilot, to the effect of "Only the British could have put two Avons into [the Scimitar] and still not have managed Mach 1"