FMC Thrust Limit Question

[Robi77 0]

FSX , PMDG-747-400 aircraftIn the FMC ( under Thrust Limit ) are the following entries:Sel OAT ToEPRUnder Sel I can enter a number.OAT always shows 15 . ToEPR shows 1.63First of all : what is OAT. I thought this is the outside temperature of a given airport but since the value remains at 15 regardless of the airport I am not so sure.Should this value not change from airport to airport ?What means EPR and it's value ?What affects the changes of a Sel number ?My goal is to establish the VR speed at different temperatures.Your help is appreciated.Hubert ( my real name )

[2009 0]

FSX , PMDG-747-400 aircraftFirst of all : what is OAT. I thought this is the outside temperature of a given airport but since the value remains at 15 regardless of the airport I am not so sure.Should this value not change from airport to airport ?What means EPR and it's value ?Hubert ( my real name )

Your definition of the OAT is correct. You can change it in the FSX Weather Menu. Definition of EPR Engine Pressure Ratio: http://www.grc.nasa.gov/WWW/K-12/airplane/epr.htmlDoes it help?

[Robi77 0]

Your definition of the OAT is correct. You can change it in the FSX Weather Menu. Definition of EPR Engine Pressure Ratio: http://www.grc.nasa.gov/WWW/K-12/airplane/epr.htmlDoes it help?

Yes it does.Thanks

[MorsAbAlto 19]

Hello Hubert,OAT stands for Outside Air Temperature. The default in Flight Simulator is set to 15

[Guest chrut]

Hello Hubert,OAT stands for Outside Air Temperature. The default in Flight Simulator is set to 15