McDonnell XHCH-1 Model 78. McDonnell XHCH-1 Model 86. The powerplant installation, derived from that developed for the XHRH-1, consisted of two 3750es hp Allison XT56-A-2 turbines mounted atop the fuselage and providing compressed-air to the 726kg thrust McDonnell 12JP20 pressure jet at the extremity of each rotor blade.
eBay