Hi

I have look at the PMDG-737NGX-Tutorial-1, (N1 LIMIT AND TAKEOFF REFERENCE DATA SETUP) and I am wondering how to program the data of:

•   SEL/OUT.

I have a clue what this values mean but how high or low can the value be, before it effect the aircraft in an incorrect way?

• 26K / 24K DERATE / 22K DERATE or 27K BUMP

How will the choice I mmake effect the aircraft?

• CLB / CLB-1 / CLB-2.

How will the choice I mmake effect the aircraft?

 

Please, answer these question in the most simplest way, thanks//

Best Fredrik

Hi frederik, will try (but I'm sure someone else will beat me to it) to give you a more detailed answer as soon as I've got time. For now suffice to say, if you go through tutorial 2 and the FCOM it's all explained there! Regards

 

 

SEL/OUT.
I have a clue what this values mean but how high or low can the value be, before it effect the aircraft in an incorrect way?

 

It's SEL/OAT.

I believe the SEL means "selected," but I know the OAT is "outside air temperature."  It's asking you to provide either a selected temperature or outside air temperature for its engine performance data.  The selected air temperature would be used in an "assumed temp" takeoff, where you're telling the automation to assume that the temperature is higher than it really is.  This forces the automation to reduce the N1 limit, which means the engines are run at a lower fan speed, reducing engine wear.

 

If you provide a value that is too high, the thrust may not be enough to get the aircraft off of the ground before you run out of available runway.  Normally, a dispatcher would provide this value.  You can also find this value by looking at runway tables.  For sim purposes, you get these values through programs like TOPCAT.

 

 

 

26K / 24K DERATE / 22K DERATE or 27K BUMP
How will the choice I mmake effect the aircraft?

 

Similar to the above, you're telling the automation to derate the amount of thrust the engine is providing.  This, again, reduces wear on the engine by not running it at its max speeds.  Similar to the above, if you derate on a short runway, you could run out of runway before taking off.  These values (for the sim) come from a program like TOPCAT (above).

 

BUMP is a setting that allows a thrust setting higher than normal in order to get better performance for shorter runways, at the cost of engine life.

 

 

 

CLB / CLB-1 / CLB-2.
How will the choice I mmake effect the aircraft?

 

Same as the takeoff derates, above, but for climb.  CLB-1 and CLB-2 run the engine at lower thrust settings, saving engine life, but also reducing climb performance.

 

 

 

All of these settings essentially reduce engine wear, but sacrifice takeoff acceleration and climb performance (with the exception of the BUMP option).  Another tradeoff is fuel: derates - takeoff and climb - end up costing you more in fuel.

Hi scandinavian13

 

Thank´s for a very detailj explanation of these things, think I have understood it in overall

 

In:

• SEL/OAT; I simply need to use the outside temp
• 26K / 24K DERATE / 22K DERATE or 27K BUMP; I must read more about it
• CLB / CLB-1 / CLB-2; Ok

Then for the manuals is an area called; Performance Dispatch and Performance Inflight? I have read that I cvan find these values into the dokument?

 

Best Fredrik

Performance Inflight

 

For example PI.30.13 and down in FCOM Vol1 - pdf page 719