Originally Posted by Sport_Pilot
That's not even close to a Clark Y. A clark Y is flat from about 15% (guessing) of the chord back.
I agree; and I added an edited retraction thinking it might be undercambered, but when the foil is rendered at 100% and 150%, it remains flat, at least on my monitor. I've rotated the plan thru 360 degrees to see if there is distortion.
It looks undercambered, but difference is less that a line width and the PDF may have an anomaly when scanned, especially since it is on the edge of the plan. There is a slight hump at about 30%, but I think it is drawing and/or scanning related.
So, unless you've got a better print, I think it's flat from the spar back. Admittedly, foils of that generation were undercambered, but this shows a slight and short hump, not the usual camber running from the LE to the TE.