Why the TIKKA's wing is so strong and lite !

Here is a chart with the right proportions for both Cri Cri and Tikka.
You can see that in order to get relatively high AR ( 8 ) Colomban used a very narrow ( 600 mm non tapered ) but extremely thick wingfoil ..over 22% thick. I took different approach and chose 17 % thick foil of my own design ( interpolated mainly from Wortmann and Eppler foils ) but it is tapered and swept and fairly wide at the root. This causes despite procentually thinner than Cri Cri foil it to be much thicker at the root by 2,4 cm ( 24 mm ). Also since the wing is tapered with wash out there are less loads at the root. This kinda wing can be constructed much lighter and still stronger if well managed. I have same AR ( 8 ) on TIKKA. 24 mm is not much..but is exactly 20% thicker than MC10 airfoil. Ask any bridge engineer how much more strenght/lightness a 20% increase will give and you'd be surprised.
TIKKA wing will have far less foils but their construction as foam/plywood is unique. Colomban wing is simpler in one aspect..it has same foil through the wing ( 35 per wing ).

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