Dailey, J. R. | Search NASA

NASA NTRS2002

Celebrating a Century of Flight

Since 1915, the National Advisory Committee for Aeronautics (NACA), transformed into NASA in 1958, has performed cutting-edge research to solve the problems of flight. Using a Grumman F4F-3 Wildcat during World War II, NACA engineers at the Langley Aeronautical Laboratory (now Langley Research Center) in Hampton, Virginia, used this aircraft to investigate the cuffs on the propeller blades to determine their efficiency. While not built to the full production standard of other Grumman Wildcats, research on this aircraft, the second F4F-3, proved most successful in advancing knowledge of the aerodynamics of this engine and propeller system. A close-up of the propeller blades with Curtiss Electric Propellers' logo is shown.

OKeefe, Sean O.↗

NASA NTRS1995

Chamber free fusion welding root side purging method and apparatus

A method and apparati are presented for non-chamber root side purging in fusion welding of oxygen reactive metals which require that the molten weld zone and local solid areas of the weld seam remaining at high temperatures be shielded from normal atmosphere to prevent degradation of the welded area. The apparati provide an inert atmosphere to the root side of a weld joint through a porous medium whereby the jet-like thrust of the plasma arc actually draws the continuously supplied inert atmosphere into the path of the molten or high temperature solid weld zone. The porous medium is configured so it can be placed at the borders of the weld seam and substantially parallel to the seam without restricting the view of the root side of the seam. The inert gas is dispersed evenly through the porous media and across the weld seam, at the point of arc penetration and in front of and behind the arc. The apparati can be constructed so as to limit the amount of inert gas flow and can be mobile and travel synchronously with the welding arc.

Dailey, J. R.↗