A320 Turbine engine data

[raptor84 2]

Hi folks,

I have a few questions regarding the Turbine engine data in the A320 aircraft.cfg file.

 

1). The part where it says fuel_flow_gain  = 0.002, is that the data that one would input for the ILDE/PERF in the FMS??? For example, at work, the ILDE/PERF is indicated our flight plan's as PERF.DEG: 02.7 (see A320 PERF-2) for our A320s or other aircraft's in our fleet for that matter. If I was to input the PERF.DEG:02.7 info into the fuel_flow_gain section to read as fuel_flow_gain = 2.7, would that be correct? I know that Aerosoft doesn't simulate inputting the IDLE/PERF in the FMS but I'm curious to know if this is another way to input the ILDE/PERF info in the aircraft.cfg file rather than in the FMS directly. I just want to know if the fuel_flow_gain is the same info as the ILDE/PERF info.

 

2). This also brings up another question. In PFPX when adding a new aircraft, under the performance settings, would the ILDE/PERF info go into both the fuel bias and hold fuel bias boxes? For example, in the fuel bias box in PFPX (see A320 PERF-4), since the fuel biases (see A320 PERF-3) is 3.2%, would I need change that from 100% to 3.2%?

 

3). In the A320 aircraft.cfg file, I've switched the engine type from the default IAE V2533-A5 to the correct IAE V2527-A5 engine to reflect more realistic to the A320 we use at work. I noticed that in the static_thrust section, it was set at 31600 and when I changed that to 26600 to reflect the correct thrust rating, I noticed that the A320 had a very slow climb to cruise altitude. For example, when I was doing a test flight from ROAH to RJCC, according to the excerpt flight plan below, it indicates that the T-O-C (FL350) is done after SARTA. However, the T-O-C for me in FSX was somewhere between AMAMI and KANAH (forgot to take screenshot). While the Mach cruise speed on A320 is M.78, both the flight plan and Aerosoft A320 were close to each other at M.76 (marked in red). In the cockpit, I left the speed as managed by the FMS not me selecting it to .78. Anyway, any thoughts to why I'm having a very slow climb? Even when I went from FL350 to FL370, normally A320 pilots have told me they use 700 fpm as I have used before making the static_thrust change but in this case, it was around 200-400 fpm.

 

The weights I was using are:

PAX        = 9,100 kgs

cgo/bag  = 3,560 kgs

ZFW       =  56,176 kgs         ZFWCG = 36.0%

fuel load =  9,500 kgs

TOW       =  65,676 kgs        TOWCG = 33.1%   TRIM = DN -1.01

 

===================================================================================

ROAH     N2611.8 E12738.8
SARTA    N2651.9 E12829.2   04  044  CLB  055  039   00.06  _____/____ 007871
       280 26061 M29 P036  030  041  369  405  0088  00.15  __________ ______
TOC      N2725.2 E12859.4   05  045  CLB  053  043   00.05  _____/____ 007576
       350 26082 M46 P055  035  037  446  501  0131  00.20  __________ ______
TAMAK    N2731.9 E12905.9   05  045  759  053  009   00.01  _____/____ 007535
       350 26082 M46 P055  035  037  446  501  0140  00.21  __________ ______
AMAMI    N2826.6 E12935.0   06  031  763  052  060   00.07  _____/____ 007244
       350 26086 M47 P041  036  022  447  488  0200  00.28  __________ ______
KANAH    N2908.1 E12941.4   04  014  764  052  042   00.06  _____/____ 007033
       350 26091 M47 P021  045  003  448  469  0242  00.34  __________ ______

==================================================================================

Attached are:

A320 PERF-1 = screenshot from FMS in FSX

A320 PERF-2 = screenshot from real flight plan indicating the ILDE/PERF info.

A320 PERF-3 = screenshot from our flight plan system indicating the ILDE/PERF info.

A320 PERF-4 = screenshot from PFPX

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[Emi 5161]

Hello,

 

the IDLE/PERF numbers in the MCDU are used to make the FMS predictions reflect the actual aircraft, with all its performance degradations that come up over the lifetime of an aircraft. No aircraft is perfectly straight, no engine always has perfect conditions, etc. These factors all play a role in the IDLE/PERF entries.

Please do not change those in our Airbus, the performance data has been programmed to reflect the engines installed.

 

The PFPX profile must not necessarily match our programmed A320 performance/fuel flow data. As we have no means to check if the base data for the PFPX profile is the same that has been used for our Airbus you can not make any conclusions regarding the numbers just by looking at our files.

 

Please do NOT CHANGE anything in the cfg files of our airplane. Any change you make may have unwanted side effects like loosing the high altitude climb capability you report. We can not support any changes to our files.