H-21B Shawnee AFFTC circa 1963

Piasecki H-21 Shawnee helicopters played an important role in the X-15 program, mainly providing a fast method of moving emergency response personnel to the site of an accident. H-21s were deployed to the launch and intermediate lakes, as well as being stationed at Edwards.

Following the A model, the USAF ordered 168 H-21Bs [51-15854..15880, 52-8665..8679, 52-8681..8709, 53-4322..4402, 54-4000..4008, 55-5127..5131, and 57-2610..2611]. The B model was equipped with the R-1820-103 Cyclone engine developing 1425 HP and had a pilot-activated, two-stage, electrically engaged supercharger.