If there’s one thing that interests me more than engine technology, it’s engine history and the Pratt & Whitney PW2037 that powers this United Boeing 757-200 at SFO has a fascinating story. In the late 1960s the USAF developed a concept for a new jet transport that would become the AMST program (Advanced Medium STOL Transport) in 1972. For the AMST, the USAF wanted a new engine under the ATE program (Advanced Turbine Engine). PW ran a demonstrator engine called the JT10D for the ATE studies. It was basically a scaled down JT9D as used on the 747. The AMST program resulted in two prototypes, the McDonnell Douglas YC-15 and the Boeing YC-15. Though AMST ended up getting canceled, work on the JT10D continued as Boeing considered a new generation 737 and an eventual 727 replacement. French company SNECMA wanted to get into commercial turbofans and was looking for a partner- Pratt was the obvious choice since at the time PW owned 10% of SNECMA, but GE offered better terms in a partnership and that resulted in the CFM56 engine. PW’s managers believed that a new generation 737 to replace the 737-200 wouldn’t sell and hesitated in developing the JT10D to compete, leaving the CFM56 as the sole engine for the 737-300 and beyond. PW then partnered with Rolls Royce to develop the JT10D further but when the 757 program was announced, Rolls Royce bailed out and offered an evolved and upgraded version of the RB.211. PW pressed on to refine the JT10D further, making it lighter, more powerful and fuel efficient. When Boeing announced the 757 program, PW’s JT10D engine was well-placed to compete with Rolls Royce and the JT10D was rebranded as the PW2000. It was the first Pratt engine with a FADEC and Delta became the PW2000 series launch customer with their 757 order. Ironically the PW2037 was selected for the McDonnell Douglas C-17 whose design benefitted from McDD’s work on their YC-15 AMST demonstrator. #Avgeek #aviation #aircraft #planeporn #KSFO #SFO #airport #SanFrancisco #California #planespotting #airlines #megaplane #instaplane #Boeing #757 #United #UnitedAirlines #N734SA #instagramaviation #splendid_transport #instaaviation #aviationlovers (at San Francisco International Airport (SFO)) https://www.instagram.com/p/B4dXuC5B9og/?igshid=1whtksrab7czu