Grumman XF6F-4 Hellcat Bu. No. 02982, at NACA Langley Field 11 May 1944 Published on June 19, 2013 in 26 June 1942Full resolution (2980 × 2555) ← Previous Next → The first prototype Hellcat was converted to the XF6F-4, seen here at NACA, langley Field, Virginia in 1944. (NASA)