Grumman XF6F-4 Hellcat: This Grumman XF6F-4 Hellcat tested while at Langley a turbo-supercharger, rather than a gear-driven supercharger as was the norm with the F6F. This aircraft served with the NACA for almost one year, beginning in the spring of 1944. NASA Identifier: L38069 (NASA Photograph.)
