Power (and speed) control

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Community-driven support for Project Airbus aircraft only.
Community-driven support for Project Airbus aircraft only.
Community-driven support for Project Airbus aircraft only.
Community-driven support for Project Airbus aircraft only.
Community-driven support for Project Airbus aircraft only.
Community-driven support for Project Airbus aircraft only.

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wmeimes
Posts: 7
Joined: 15 Sep 2014, 08:03

Power (and speed) control

Post by wmeimes »

Gentlemen

I'm having trouble to manage speed in Project Airbus models. For example, I set 0.72 mach at 32000ft with AP Autothrottle Speed and Height buttons pressed. The model a (A319), gets there, but then keeps on accelerating because it seems autothrotlle is't controling the engines that keep on running the same regime so I right away go overspeed. That also happens in lower levels with lower speeds, (18000 ft at 370 knots, for example).
I fly commercial birds with Pro-Atc/X so speed control is critical.

Thanks in advance
Walter

esg
Posts: 1591
Joined: 01 Jul 2009, 22:03

Re: Power (and speed) control

Post by esg »

Try using the A320's air file.

wmeimes
Posts: 7
Joined: 15 Sep 2014, 08:03

Re: Power (and speed) control

Post by wmeimes »

I'll try latter but if i'm not wrong, yesterday I made a few tests with A320, with the sam (bad) results. But I confirm that latter.

wmeimes
Posts: 7
Joined: 15 Sep 2014, 08:03

Re: Power (and speed) control

Post by wmeimes »

320 also doesn't work.same problem. I tweaked cfg to more power, and the problem gets worse. Auto throtlle doesn't work, engines don't stop to acelerate and the plane goes overspeed
Tweaks (from Airbus Project forum)
You can try these new air files (CFM and IAE version) with new N1 curves and real power value :

https://rapidshare.com/files/694929417/ ... curves.zip
so You must edit each aircraft.cfg file to change some value :

For the CFM version :

[GeneralEngineData]
engine_type=1
fuel_flow_scalar=1.086
Engine.0=13.500000,-18.95,-5.125
Engine.1=13.500000,18.95,-5.125
min_throttle_limit=-0.25

in the autopilot section , check that :
[autopilot]
autothrottle_max_rpm=96.5



[TurbineEngineData]
fuel_flow_gain=0.00247
inlet_area=25.3000
rated_N2_rpm=16000
static_thrust=27000 // CFM56-5B4 engine 120Kn thrust update by francois Dore with Airbus industrie data
afterburner_available=0
reverser_available=1
bypass_ratio=5.70 // bypass ratio CFM Engines







For IAE version :

[GeneralEngineData]
engine_type=1
fuel_flow_scalar=1.086
Engine.0=13.500000,-18.95,-5.125
Engine.1=13.500000,18.95,-5.125
min_throttle_limit=-0.25
max_contrail_temperature=-30


in the autopilot section , check that :
[autopilot]
autothrottle_max_rpm=96.5


[TurbineEngineData]
fuel_flow_gain=0.00247
inlet_area=22.6000
rated_N2_rpm=14950.000000
static_thrust=26600.000000 // IAE v2527-A5 26500 Lbs - 117.88Kn update by francois Dore with Airbus industrie data
afterburner_available=0
reverser_available=1
bypass_ratio=4.80 // bypass ratio IAE Engines

wmeimes
Posts: 7
Joined: 15 Sep 2014, 08:03

Re: Power (and speed) control

Post by wmeimes »

It seems I found the solution :) . The problem seems to be in mach button. Disregard the mach button, and keep using speed settings in knots, that can be verified in TAS at main flight display, because speed meter in project airbus birds is limited to 400 kn. Works perfectly until ceiling height and cruise speed limits.
I guessed this could be the problem because I made some progressive tests from 250 kn until level 100 to 400 kn lvl 200 with no problem. When I switched to mach refference, the bird went mad.
Now it would be interesting to find what's wrong with mach button, because this is how we should use above a certain speed (maybe 400 kn) the refference in mach.

Regards
Walter

American398
Posts: 13
Joined: 17 Jan 2010, 21:37

Re: Power (and speed) control

Post by American398 »

I seem to be having the same issue, the autopilot holds the IAS ok but when you switch to mach it does not hold. you can fly ias up to about 27 or 28000 before you have to switch to the mach speed, which is .78. its gotta be something with the default a321 panel because i tested it with the 737 panel and it holds the mach just fine. anyone know of any solutions?

Airbusjoerg
Posts: 2
Joined: 26 Nov 2014, 19:03

Re: Power (and speed) control

Post by Airbusjoerg »

wmeimes wrote: You can try these new air files (CFM and IAE version) with new N1 curves and real power value :

https://rapidshare.com/files/694929417/ ... curves.zip
The Download-Link is no longer active. Please, I need this new air-file for my homecockpit (www.cockpit-simulation.de). Is someone able to provide a working download-link? Would be GREAT!!

Best regards
Jörg

Airbusjoerg
Posts: 2
Joined: 26 Nov 2014, 19:03

Re: Power (and speed) control

Post by Airbusjoerg »

No one here?

WarthogCC
Posts: 9
Joined: 21 May 2015, 21:22

Re: Power (and speed) control

Post by WarthogCC »

wmeimes wrote: You can try these new air files (CFM and IAE version) with new N1 curves and real power value :

https://rapidshare.com/files/694929417/ ... curves.zip

Does anyone have this file since Rapidshare is gone?

fdd_fr
Posts: 1764
Joined: 03 Jan 2012, 16:02

Re: Power (and speed) control

Post by fdd_fr »

Change air file is not the solution.

Default FSX autopilot has a huge problem : It doesn't calibrates Mach versus IAS when you change your altitude.

If you toggle in mach mode with default autopilot, it memorize the IAS value when you have switches to mach mode and if you climb it keep this IAS value, so this is mandatory, you will do an overspeed, because during climb, at constant mach, IAS value must decrease with altitude.
At 29000 feet, Mach 0.77 is close to 300 KIAS
At 35000 feet, Mach 0.77 is close to 275 KIAS.

So FSX doens't decrease the IAS value when you climb.


You have 3 solutions :
- use only mach mode when you cruise (with FSX default Aircraft); Not during climb or descent.
- use a payware aircraft
- use FD-FMC panel, which has an autopilot that works in real Mach mode with automatic calibration of the IAS value versus Mach value, according altitude.

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