John W. and John Mc. have it exactly right–the FAA can’t set a standard without having the technical expertise first.
If fuel efficiency WAS possible–don’t you think that the industry would cash in on this knowledge–selling new airframes and engines?
Instead, the government is proposing to “help” us (kind of like the government-owned Russian airframe manufacturers “help” that industry!) (laugh)
Another example of government “group-think”. In the Army, the standard joke about substandard equipment was “A Camel is a Horse designed by Committee!”