Pratt & Whitney announced a new jet engine that will be 12-15% more efficient than current models.  Aircraft efficiency is more difficult to increase because the planes are already lightweight, and fly at constant speeds.  A 15% improvement is a big deal.

In commentary, private industry continues to whine about government regulation, and at the same time engineer exciting technical improvements that address the regulations.  My take:  never never never trust a company that says it cannot do something when it is in their short-term interest to say so.  Additional Reading.