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smoki
07-04-2007, 10:26 PM
Hi, I encountered a problem in offsets for n1 and n2 of B744 (MSFS 2004). I managed to get the offsets of EGT and EPR , and control them (increasing and decreasing) their values on EICAS. However, I cannot do the same thing on n1 and n2, using the same method.
These are the offsets that I managed to find for n1 and n2:
0898 for n1 and 0896 for n2.

This is the logics that I wrote:

if EngSwitch
Eng1n1 = counter 16384 100 //Eng1n1 = 0898
Eng1n2 = counter 16384 100 //Eng1n2 = 0896
else
Eng1n1 = counter 0 100
Eng1n2 = counter 0 100
endif

I used the same method for EGT and EPR and It works.

Can I clarify with you if the offsets that I used are correct and can anyone help me do correction to the logics above if I had written it wrongly?

Thank you very much for your help

Trevor Hale
07-05-2007, 07:53 AM
Well, I am not exactly sure what your trying to do, but are you sure that your variable names are correct? Did you change them? Your offsets look right. I am just trying to understand your Logic, I guess if I saw more maybe I could figure what your trying to accomplish.

You have Eng1n1 & Eng2n1


I have the variables below.

fs1n1 = engine 1 N1 Value
fs2n1 = engine 2 N1 Value.

How were you able to get EGT to display on the Upper Eicas?

Best regards,

Trev

Bob Reed
07-05-2007, 09:54 AM
Sounds to me like someone is working on there own software.........?? :)

smoki
07-09-2007, 01:21 AM
Well, I am not exactly sure what your trying to do, but are you sure that your variable names are correct? Did you change them? Your offsets look right. I am just trying to understand your Logic, I guess if I saw more maybe I could figure what your trying to accomplish.

You have Eng1n1 & Eng2n1


I have the variables below.

fs1n1 = engine 1 N1 Value
fs2n1 = engine 2 N1 Value.

How were you able to get EGT to display on the Upper Eicas?

Best regards,

Trev

Hi, I am writing exactly the same with the one I write for N1 and N2.
Offsets for EGT and EPR are as follow:
08BC 2 E1EPR
08BE 2 E1EGT
It works... and I still haven't got the solution to make the N1 and N2 rise.

fs1n1 and fs1n2 are the ones inside sysvar with xxxx offsets rite? Do you know what xxxx means? I read the comment in the sysvar that says these offsets are handled internally.

Regards,
Smoki

Trevor Hale
07-09-2007, 07:44 AM
Yes,

I am under the impression, and I hope I am wrong, because I am intrigued with your quest here. I didn't think you can change FS1n1 and Fs2n1 etc.
Hence offsets are handles internally. You coul probably read them, just not write to them.

If you find out the solution to this problem, please let em know. I would like to change my N1 and N2 values to something that suits my aircraft better.

Best regards,

Trev

Bob Reed
07-09-2007, 08:46 AM
Actually, now I may be wrong it was a long time ago... Seems Enrico used to scale the N1 for one of his softwares. Now I may be off on this but I do seem to recall that but how it would be done is WAY beyond me.

Bob Reed
07-09-2007, 08:49 AM
You know what , it was the Boeing package and you could scale the N1 and N2 so you could use it with turbo props. I do not remember how but that is what it was. I am sure the software is capable of doing it still, just have to find out how.

smoki
07-09-2007, 09:42 PM
You know what , it was the Boeing package and you could scale the N1 and N2 so you could use it with turbo props. I do not remember how but that is what it was. I am sure the software is capable of doing it still, just have to find out how.

Hi Bob,

I don't quite understand what you mean by scaling the N1 and N2. I read from the FSUIPC offset list (0898), it mentions about calculation for Prop RPM (multiplying by RPM scaler). Is that what you mean? And I am working on B747-400, do you think that I must use RPM scaler to control my N1 and N2? Thank you

Regards,
Smoki

Bob Reed
07-09-2007, 11:03 PM
No!! N1 and N2 should be there when the engines are running. What 747 are you using? Something is not right there.

smoki
07-10-2007, 09:27 PM
No!! N1 and N2 should be there when the engines are running. What 747 are you using? Something is not right there.

Hi Bob,

I am using 747-400 from MSFS 2004. The N1 and N2 indication are rising when the engines are started. However, I want to control the N1 and N2 just by switching a switch to ON position, without starting the engines. It can be done for EPR and EGT but not for N1 and N2 (using the logics posted previously).

regards,
Smoki