Question to the engine experts.
Contrarotating cores has been the latest big step in commercial engine design.Both GE and Rolls (and P&W) accept that contra rotating fans or "Open Rotors" is a must for a further leap in efficiency.
Question.Could one take the 2 contra rotating shafts on the core to directly power the 2 contra rotating sets of blades (shrouded or not ) and thus eliminate all the complicated gearing that would otherwise be necessary?
GE has 2 shafts and RR could pick 2 of 3.
Prior to contra rotating cores there was no option.I just wondered whether this new technology might well fit in with the next leap forward at the "front end"?