
So the way I'm getting it is, both designs were next gen in their own way, Achieving or exceeding the required 35,000 lbs thrust levels.
The YF-120 used a variable bypass method which could increase efficiency in some parts of the envelope.
The YF-119 used a more traditional approach but with more advanced cooling techniques and blisk rotors to reduce compressor stages.
A few questions tho.
1. Did the reduction of compressor stages contribute to the YF-119s efficiency over the YF-120 in other parts of the envelope. But the YF-120 had even less stages, 2 fan and 5 HP stages to the 119's 3 fan and 6 HP stages.
So how is Pratt achieving so much efficiency (at some parts of the envelope) with their design, in other words whats their secret sauce?
2. As far as i know the YF-120 chose to go with a Variable cycle design specifically for efficiency on different flight profiles. Did Pratt simply take a different approach to achieve their efficiency targets or was the fact that the YF-119 was more efficient than the YF-120 on some altitudes simply the result of the YF-120 being less mature.
3. Was the Blisk rotors responsible for the reduction of compressor stages, if so, why does the GE-F110 have more than 10, (I think 12) despite using Blisk rotors too and did the YF-120 use them too?
The YF-120 used a variable bypass method which could increase efficiency in some parts of the envelope.
The YF-119 used a more traditional approach but with more advanced cooling techniques and blisk rotors to reduce compressor stages.
A few questions tho.
1. Did the reduction of compressor stages contribute to the YF-119s efficiency over the YF-120 in other parts of the envelope. But the YF-120 had even less stages, 2 fan and 5 HP stages to the 119's 3 fan and 6 HP stages.

So how is Pratt achieving so much efficiency (at some parts of the envelope) with their design, in other words whats their secret sauce?
2. As far as i know the YF-120 chose to go with a Variable cycle design specifically for efficiency on different flight profiles. Did Pratt simply take a different approach to achieve their efficiency targets or was the fact that the YF-119 was more efficient than the YF-120 on some altitudes simply the result of the YF-120 being less mature.
3. Was the Blisk rotors responsible for the reduction of compressor stages, if so, why does the GE-F110 have more than 10, (I think 12) despite using Blisk rotors too and did the YF-120 use them too?