March 28
The notebook of the Wright brothers who changed history for ever
In my recent visit to the Franklin Institute in Philly, I had the opportunity to take a look at the notebook used by the Wright Brothers and the first drag measurement counter balance, which was used by the brothers to estimate drag of various airfoil sections, using wind tunnel testing. The no. 12 section used by the brothers was found to have low drag and high lift, in comparison to the other sections which were tested. The No. 12 section later on was used in the first manned flight of 1903.
[Featured title image source: http://www.uscg.mil/history/faqs/Wright_Brothers.asp]