Slingsby T53 design
Answers to various questions I have put to Dad on the T53 have been answered thus:
"calculations could have been done on flight handling and structure but were not deemed necessary-what had worked for them in the past was used.Air Ministry data was used ,for rib spacing calculations could have been done on skin buckling but were not."
He then told me what happened after he left and a weight saving redesign was done but I do not intend to put it on the internet!
Dads design for the spar, which was laminated and bolted was based on his previous job at a firm of structural steelworkers and was done for cheap manufacturing but was redesigned by Pat Monk using machined components and put up the cost considerably.
I presume "Air Ministry data" was some kind of design bible.