Full-Scale Tunnel (FST), NASA history collection

Modification of entrance cone of the Full-Scale Tunnel (FST). To the left are the FST guide vanes which Smith DeFrance described in NACA TR No. 459: "The air is turned at the four corners of each return passage by guide vanes. The vanes are of the curved-airfoil type formed by two intersecting arcs with a rounded nose. The arcs were so chosen as to give a practically constant area through the vanes." (p. 295) These vanes "have chords of 3 feet 6 inches and are spaced at 0.41 of a chord length. By a proper adjustment of the angular setting of the vanes, a satisfactory velocity distribution has been obtained and no honeycomb has been found necessary." (p. 295). Close inspection of the photograph will reveal a number of workers on the scaffolding. The heights were great and the work was quite dangerous. In October 1930, one construction worker working on the roof of the tunnel would die when he stepped off the planking to fetch a tool and fell through an unsupported piece of Careystone to the floor some 70 feet below.

NASA Identifier: L5690