Thickness, measured by Hugh B. Freeman, of the Boundary Layer on the 40th model of the Akron airship. This image is from the NACA Report No. 430 of Hugh B. Freeman : Measurements of flow in the boundary layer of a 1/40-scale model of the US airship Akron <a rel="nofollow" class="external free" href="https://ntrs.nasa.gov/search.jsp?R=19930091507">https://ntrs.nasa.gov/search.jsp?R=19930091507</a>. The author has found a transition evidence of the Boundary Layer (from the laminar state to the turbulent state) a little ahead of the station 0. This rapid transition could be due to the turbulence of the Langley's Full Scale Wind Tunnel (now destroyed).
<a href="//commons.wikimedia.org/wiki/User:Bernard_de_Go_Mars" title="User:Bernard de Go Mars">Bernard de Go Mars</a>
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