The Rescue of Bat 21 by Darrel Whitcomb, Military Aviator and Decorated SEA veteran. The author not only has "researched" the story, but was there "in it". This is the BEST book on the  BAT 21 SAR ... period. This hugely complicated SAR took place amid the massive North Vietnamese invasion of the South , when BAT 21 an unarmed EB-66, was shot down by a SA-2, commencing a  SAR that was fully interwoven with the massive land battle going on below it. Hard bound. Inscribed by the  author.