What were/are the military designations of the JT8D and PW4000? Turbine engines on U.S. military aircraft, in addition to their manufacturer-given names, receive separate designations (consisting of J [for turbojets], F [for turbofans; formerly TF], or T [for turboprops], followed by a number) for internal military use (examples: JT3C/J57, JT4A/J75, JT3D/TF33, JT8A/J52, JT9D/F105, PW2000/F117, JT12A/J60, CJ805-3/J79, CJ610/J85, CF700/TF37, CF34/TF34, CFM56/F108, CF6/F103), even if the military engine is completely unchanged from the civilian version known universally by the manufacturer-given name.
For most engines, information on their various names is readily available; however, I have been unable to find the military designations of two Pratt &amp; Whitney turbofans currently-or-formerly-used on U.S. military aircraft (the JT8D low-bypass turbofan, used on the T-43, C-9, and YC-15, and the PW4000 high-bypass turbofan, used on the KC-46).  Does anyone here know the answers to this puzzle?
Two versions of license built military JT8D is called RM-8A and RM-8B.
PW4062 is a military version of PW4000 used in Boeing KC-46 Pegasus.