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P3D v4 Adding a Row to a Performance Table in Aired

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us-texas
Hi all. Definitely an amateur here. I'm using Aired 1.52 to try to edit an aircraft in P3D for more realistic taxi behavior - more realistic breakaway thrust, etc. I'm using table 1506 and the problem is there aren't enough mach values available in order to pinpoint low-mach behavior without impacting flight characteristics. I'd like to insert a new row of mach value in between 0 and .50. Is there a way to do this? Thanks!
 
I think the size of those tables is fixed. Many have complained about not having enough rows.
 
Thanks, but my question is how to actually add another row. The airplane I'm editing only has .00, .50, and .90 lines. I'd like to add a .05 or .10, somewhere in there, so I can isolate my edits to taxi behavior.
 
I don't know about Aired.

First check how many rows the table can have. I see the FSX 737 has 20 rows for the 1506 table. Is this how many you have? If you have less you could try copying the 1506 table from the 737 into your aircraft. Again, I don't know Aired, I use Aircraft Airfile Manager V2.2 which does allow you to copy tables from one aircraft to another and that is something I have used in the past to get higher definition tables.

The other option is to write an assemby file (.asm) and compile it with the necessary number of rows and then use AAM to copy that table into your own aircraft (again I don't know if Aired can do this). Examples of assembly files and the tool to convert them in .air files is in the P3D SDK.
 
Sorry, my mistake, I meant columns. Only a mach .00, .50, and .90 column for the aircraft I'm trying to edit.
 
The table in question will support a max of 21 rows and 11 columns. The rows would correspond to the CN1 value and the columns would correspond to the mach number. That means you can have up to 21 entries for CN1 and up to 11 entries for mach. Here's an example obtained from the Prepar3D website:

Code:
          ;N1 vs Thrust table (max 21 rows, 11 columns)
          ; NOTE: While generally insignificant with turboprops,
    ;       exhaust thrust can be modeled here                 
    ;IN: X: Mach
    ;IN: Y: N1 (corrected)
    ;OUT: Gross Thurst (corrected) / static thrust
        TOKEN_BEGIN     AIR_70_N1_AND_MACH_ON_THRUST

        UINT32 3,3     ;ROWS,COLS
    ;        N1
        REAL8    0.0,      0.0,        0.9 ; Mach
        REAL8    0.0,  0.00000,    0.00000
        REAL8  100.0,  0.00000,    0.00000

        TOKEN_END
 
Typically 1506 has data for sea level zero airspeed (zero Mach) and sea level high Mach. The first describes the static thrust performance of the engine for different values of N1. If your idle thrust is too high, you can decrease it by reducing the value in 1506. However you cannot reduce it below a value which will not allow the engine to run. (I forget exactly what that is). Depending on the engine you may be able to lower N1 at around Idle while maintaining a higher N2. You would do this in 1502. Remember, thrust varies directly with N1 while N1 and N2 can differ. So you may be able to fix an excessive idle thrust issue by just lowering the idle N1 leaving N2 the same.
Roy
 
Thanks guys. I've mostly achieved the result I was looking for by changing the friction coefficient in sim1.dll and altering table 1506 accordingly. There is still a hard-coded minimum fuel flow that is a bit more than reality, but it's a lot closer than before and I didn't feel like diving deeper into more tables and having to fine-tune inflight fuel burns to counteract any adjustments there.
 
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