ICAO's LTO power settings vs N1
Hi,
Particularly in the emission studies I frequently encounter this power settings issue. According to the ICAO the standard power settins are:
7% idle
30% approach
85% climb
100% takeoff
Most of the researchers accept this power settings and evaluate the emissions with this settings.
What I would like to know is what is that actually? Is it something about throttle? Thrust resolver angle?
What is the relationship between the power settings and the N1 (if there is! / it should be to me).
I understand that they note the maximum takeoff power (or may be I should say thrust) as 100% and scale other power settings against to this %100 but how. For instance, I read from FDR, an average N1 is around 22-24% (standard deviation is around 2%) for CFM56-7B26 series engine, then what is the relationship between the 7% and 22% ? I dont expect a strict relationship exists, since the ICAO numbers include all of the engine or aircraft tpyes, but there must be a relationship.
Can we discuss these issues please?
Thank you.