David,
Glad you don't mind my building on your excellent foundation!
I flew a new type today (Cubair's DA40 - very nice) and in adding it to the spreadsheet discovered I'd left out some formulae.
I've corrected the downloadable ones, but if anybody has already dowloaded it, you need to highlight the row of cells from F8 to AD8 and drag them down to row 15 (calls F15 to AD15) to copy the formulae into the empty cells.
Sorry about that
