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  1. J

    Table 1505

    I'll see what I can do. The equations for RPM are beyond the scope of the document (and my knowledge) and because of shaft friction, RPM affects torque spool up. I'll still provide the equations for torque though, but without the RPM equations. The sad part about torque is that there's a...
  2. J

    Table 1505

    It comes from the air-files. The table data blocks found in air-files always contain the following information: ID (4 bytes) Size (4 bytes) Data (varying size) The sim uses the ID to figure out what table is what. 0x154B is the ID that asm2air.exe assigns to AIR_P3DV440_CORRECTED_N1_FROM_FF...
  3. J

    Table 1505

    I'm still working on the document. Let there be no mistake - it will be released. I just want to avoid as many silly mistakes as possible so I'm currently retesting all of the equations in all situations I can come up with.
  4. J

    Table 1505

    That's the table I'm referring to. TOKEN_BEGIN AIR_P3DV440_CORRECTED_N1_FROM_FF is the token for table 154B. It fills the exact same purpose as 1505 but the input is CFF instead of CFF/static_thrust. That table is hardcoded (but with slightly different values) in all sim versions prior to v4.4...
  5. J

    Table 1505

    Technically, they didn't specifically say that it replaced that table so no they are not wrong. They only said that you could have more than one fuel_flow_gain: The only way to override the hardcoded table is to use 154B in P3Dv4.4 and newer. Prior to 4.4, it was completely impossible to...
  6. J

    Table 1505

    That's not the table(s) I'm talking about. That's fuel_flow_gain.n and means that you can make fuel_flow_gain vary with CN1/CN2 (depending on turboprop or jet). This has nothing to do with the hardcoded "1505" table used by turboprops to calculate a new target CN1 based on CFF. That table can...
  7. J

    Table 1505

    Are you sure? I know about table 154B but that's found in the .air-file, however I can't find anything like that in aircraft.cfg while browsing the P3Dv4 SDK. fuel_flow_gain.n can be set in the aircraft.cfg file though.
  8. J

    Table 1505

    I have reviewed pretty much everything and there's one thing I'm not entirely sure about. The turboprop CN1 calculation uses a hardcoded 1505 equivalent. I've managed to get a hold of that table through experimentation for both FSX and P3Dv4.4 (which now also supports custom ones) The question...
  9. J

    Table 1505

    I'm thinking I might expand the document to also cover turboprops and helicopters. Both use the turbine system and engine spool for the turbine itself works the same way more or less. The difference is that CN1 is used instead of CN2 and of course that the 1505 table is hardcoded. I will not...
  10. J

    Table 1505

    I'm working on a document where all of my findings will be included. I will also provide an Excel-sheet with measured CN2 values from the sim compared to calculated ones.
  11. J

    Table 1505

    CN1 is not independent from CN2. CN1 is like mentioned calculated using 1502 and a P-controller / first order lag filter. (not sure what the best name for it is) 1505 affects spool rate, yes, but not by getting some kind of spool rate of change. It is a look-up table for a new target CN2. By...
  12. J

    Table 1505

    Yes correct, CN1 is calculated using 1502, but the response is not instantaneous because a P function is applied to add some lag to it. Probably to simulate inertia. Thrust is not part of the CFF calculation. Make 1505 completely flat at CN2 30% and look what happens to CFF. It will increase...
  13. J

    Table 1505

    I've verified the engine spool equations for a running engine. I think I've got the start up and shutdown situations covered now. Just gonna run some tests just to make sure. Exactly how the information can be applied to aircraft development is something I'm not entirely sure about, that part...
  14. J

    Background image

    It's working, I was using an older version.
  15. J

    Table 1505

    I'll provide full equations once I've double checked them. Like I said, we did this research almost 3 years ago. The general concept is the following though: 1. Get a target CN2 from 1503 & 1504. 2. Calculate CFF (corrected fuel flow) based on current CN2, current CFF, target CN2...
  16. J

    Table 1505

    I just reviewed my notes and I need to look up some stuff. For a running engine, everything's okay, however engine start prior to combustion and engine shutdown doesn't seem to be entirely covered yet.
  17. J

    Background image

    It doesn't work. When I zoom in, I can't see anything but gray.
  18. J

    Background image

    Okay, not sure I follow you. You mean it's possible to extract background images from SBuilderX along with coordinates that can then be imported in ADE?
  19. J

    Table 1505

    Reviving an ancient topic. Has 1505 and fuel_flow_gain been fully explained somewhere since I created this thread? The reason why I'm asking is simply that I teamed up with Yves a 3 years ago and we were able to figure out exactly how engine spool rate is simulated on jet engines in MSFS/P3D. By...
  20. J

    Background image

    Hello, I've been away from airport design for a few years and now I'm picking it up again. Back when I was active I used https://www.ptsim.com/sbuilder/gmaps.htm for background images, however that tool seems broken. What do you use to get background images and coordinates for the corners nowadays?
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