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Jet Engine Performance

1506 and 1507: Two philosophies.

1) 1506 set up without ram drag; set ram drag in 1507.

2) 1506 set up with ram drag; 1507 zeroed out.
 
Who ever said 1505 affects drag etc has no clue what they are talking about...

"^^^
This is pretty much how I use and interpret it. Only diff is in my experience, the starter spool is also affected. I'll take a look at it again some day.
-Pv-"


yes thats what I mean by light off RPM.... light off is the point you want combustion to occur. If you set the first (left) column to zero, upon ignition, CN2 will fall to zero then spool according to time to next line. If you set it to idle CN2, it will spike up to idle instantly.
 
RW Beechjet JT-15 Engine Spool.

FS9 Beechjet JT-15 Engine Spool reworked.


Record: 1505 *FS2000 Turbine Jet Table N? vs Y (Reworked)
Points: 10
0.000000 0.000000
0.000000 10.000000
0.050000 24.000000
0.150000 30.000000
0.250000 40.000000
0.350000 50.000000
0.500000 60.000000
0.650000 80.000000
0.800000 90.000000
1.000000 96.000000
upload_2015-1-29_17-52-12.png


FS9 Beechjet JT-15 As shipped

Record: 1505 *FS2000 Turbine Jet Table N? vs Y (As shipped)
Points: 10
0.000000 0.000000
0.002940 10.000000
0.011800 30.000000
0.020660 40.000000
0.033970 50.000000
0.053170 60.000000
0.133910 70.000000
0.290000 80.000000
0.440000 90.000000
0.570000 108.000000

upload_2015-1-29_18-6-19.png



This is what I have so far. Fairly close on the 1505.
 
Last edited:
mgh said:
The values for Table 1505 are not surprisingly the same in both my copies of ESP and P3D SDKs. Both are identical to the FSX default B747 .air file.

The table from the SDKs is:

Code: 
;N2 (Corrected) vs. FuelFlow constant
    ;  where the constant is a normalized ratio of actual fuelflow parameter to static thrust
    ;IN:  Normalized Fuelflow constant
    ;OUT: N2 (corrected)
        TOKEN_BEGIN     AIR_70_CORRECTED_N2_FROM_FF

        UINT32 10

        REAL8   0.00000,       0.0
        REAL8   0.00294,      10.0
        REAL8   0.01180,      30.0
        REAL8   0.02066,      40.0
        REAL8   0.03397,      50.0
        REAL8   0.05317,      60.0
        REAL8   0.13391,      80.0
        REAL8   0.25771,      90.0
        REAL8   0.54000,     100.0
        REAL8   0.68686,     105.0

        TOKEN_END

This is plotted in the attached figure.

I still don't know its purpose - does anyone?
Click to expand...
Isn't that the famous 1505 curve that causes engine surge on start-up?

For what it's worth this is mine for the RR conway 550 which is "inverted" with 105%CN2 max.
It works a dream. Ignition is set at just above 24% and idle in ISA is 56%

Record: 1505 Turbine CN2 vs fuel flow
Points: 10
X .................Y
0.000000 24.100000
250.000000 29.400000
509.000000 36.733500
623.440000 41.158800
688.370000 45.568700
754.300000 52.301900
818.230000 61.889700
881.160000 73.001200
944.090000 88.043100
1005.020000 104.999700
 
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