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Airbus A320 [Family]

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Re: Airbus A320 [Family]

Postby HelldiverSquadron » Tue Feb 04, 2014 1:29 am

Hooray: Aye, no worries. I tend to shy away from conflict, but this thread was important and I wanted to see the progress with this wondrous aircraft.
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Re: Airbus A320 [Family]

Postby HelldiverSquadron » Tue Feb 04, 2014 1:30 am

I say we just go back to before conflict and address what the problems really are. Pitch, etc.
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Re: Airbus A320 [Family]

Postby FGRS » Thu Feb 06, 2014 8:04 pm

Guys I need help here,so please,please take a moment and at least try to help me out. The pitch/dive behavior is out. BUT now the problem is that the aircraft,A321 more then all others,have this problem:

Even with very little fuel,pax and cargo,this aircraft needs way to much to take off. With outer/inner fuel tanks full,and 40% fuel in the central fuel tank,it needs about 4km to take off. Even worse is when the aircraft is in the air. the IAS od 250 kts is barely enough for the aircraft to climb.

With the flaps retracted ,the pitch is way up high. At 280 KIAS or more the pitch is better ,but still high. So the landing is quite simply impossible. On 230kts IAS for example the pitch is even more up high ...
So ,can anyone help me out how to fix this,where the hell is the problem with this aircraft? It looks like that this aircraft's wings are more like it's hstab.
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Re: Airbus A320 [Family]

Postby HelldiverSquadron » Thu Feb 06, 2014 8:21 pm

4 Km???? Maybe get a whole new download. I don't have that problem and I use standard AoA for t/o when doing so. do you have at least 2* of flaps?
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Re: Airbus A320 [Family]

Postby FGRS » Thu Feb 06, 2014 8:43 pm

Man,am I the only in this damn world to have these problems? The aircraft had a terrible pitch/dive problems,it was completely unable to fly. With that fixed,there is this. I was asking for help here.

This is the A321-211.mxl
Code: Select all
<?xml version="1.0"?>
<?xml-stylesheet type="text/xsl" href="http://jsbsim.sourceforge.net/JSBSim.xsl"?>
<fdm_config name="A320-211" version="2.0" release="BETA"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:noNamespaceSchemaLocation="http://jsbsim.sourceforge.net/JSBSim.xsd">

<fileheader>
   <author> Unknown </author>
   <filecreationdate> 2003-01-01 </filecreationdate>
   <version> Version </version>
   <description> Airbus A320 </description>
</fileheader>

<metrics>
   <wingarea  unit="FT2"> 1319.79 </wingarea>
   <wingspan  unit="FT" >  111.26 </wingspan>
   <wing_incidence>          1.03 </wing_incidence>
   <chord     unit="FT" >   13.76 </chord>
   <htailarea unit="FT2">  334.24 </htailarea>
   <htailarm  unit="FT" >   57.88 </htailarm>
   <vtailarea unit="FT2">  248.79 </vtailarea>
   <vtailarm  unit="FT" >   57.33 </vtailarm>
   <location name="AERORP" unit="IN">
   <x> 642.122 </x>
   <y> 0 </y>
   <z> -25.2091 </z>
   </location>
   <location name="EYEPOINT" unit="IN">
   <x> 80 </x>
   <y> -30 </y>
   <z> 70 </z>
   </location>
   <location name="VRP" unit="IN">
   <x> 661.1 </x>
   <y> 0 </y>
   <z> -37 </z>
   </location>
</metrics>

<mass_balance>
   <ixx unit="SLUG*FT2">    611903 </ixx>
   <iyy unit="SLUG*FT2">   1735389 </iyy>
   <izz unit="SLUG*FT2">   2301293 </izz>
   <ixy unit="SLUG*FT2">         0 </ixy>
   <ixz unit="SLUG*FT2">         0 </ixz>
   <iyz unit="SLUG*FT2">         0 </iyz>
   <emptywt unit="LBS" >     87274 </emptywt>
   <location name="CG" unit="IN">
   <x> 642.122 </x>
   <y> 0 </y>
   <z> -41.7398 </z>
   </location>

   <pointmass name="Crew">
      <weight unit="LBS">600</weight>
      <location name="POINTMASS" unit="IN">
         <x>400</x>
         <y>0</y>
         <z>0</z>
      </location>
   </pointmass>
   <pointmass name="PAX">
      <weight unit="LBS">75500</weight>
      <location name="POINTMASS" unit="IN">
         <x>705</x>
         <y>0</y>
         <z>0</z>
      </location>
   </pointmass>
</mass_balance>

<ground_reactions>
   <contact type="BOGEY" name="NOSE_LG">
   <location unit="IN">
      <x> 29.566964</x>
      <y> 0 </y>
      <z> -137.9617 </z>
   </location>
   <static_friction> 0.5 </static_friction>
   <dynamic_friction> 0.8 </dynamic_friction>
   <rolling_friction> 0.02 </rolling_friction>
   <spring_coeff unit="LBS/FT"> 75000 </spring_coeff>
   <damping_coeff unit="LBS/FT/SEC"> 16978.5 </damping_coeff>
   <max_steer unit="DEG"> 75 </max_steer>
   <brake_group> NONE </brake_group>
   <retractable>1</retractable>
   </contact>
   <contact type="BOGEY" name="LEFT_MLG">
   <location unit="IN">
      <x> 699.9243 </x>
      <y> -149.4094 </y>
      <z> -152.6824 </z>
   </location>
   <static_friction> 0.5 </static_friction>
   <dynamic_friction> 0.8 </dynamic_friction>
   <rolling_friction> 0.02 </rolling_friction>
   <spring_coeff unit="LBS/FT"> 180000 </spring_coeff>
   <damping_coeff unit="LBS/FT/SEC"> 33957 </damping_coeff>
   <max_steer unit="DEG"> 0.0 </max_steer>
   <brake_group> LEFT </brake_group>
   <retractable>1</retractable>
   </contact>
   <contact type="BOGEY" name="RIGHT_MLG">
   <location unit="IN">
      <x> 697.3425 </x>
      <y> 149.4094 </y>
      <z> -152.6824</z>
   </location>
   <static_friction> 0.5 </static_friction>
   <dynamic_friction> 0.8 </dynamic_friction>
   <rolling_friction> 0.02 </rolling_friction>
   <spring_coeff unit="LBS/FT"> 180000 </spring_coeff>
   <damping_coeff unit="LBS/FT/SEC"> 33957 </damping_coeff>
   <max_steer unit="DEG"> 0.0 </max_steer>
   <brake_group> RIGHT </brake_group>
   <retractable>1</retractable>
   </contact>

   <contact type="STRUCTURE" name="NOSE_1">
   <location unit="IN">
      <x> 205.905536 </x>
      <y> 0 </y>
      <z> -38.1374 </z>
   </location>
   <static_friction> 1.0 </static_friction>
   <dynamic_friction> 1.4 </dynamic_friction>
   <rolling_friction> 1.0 </rolling_friction>
   <spring_coeff unit="LBS/FT"> 1.5e+06 </spring_coeff>
   <damping_coeff unit="LBS/FT/SEC"> 50000 </damping_coeff>
   <max_steer unit="DEG"> 0.0 </max_steer>
   <brake_group> NONE </brake_group>
   <retractable>0</retractable>
   </contact>
   <contact type="STRUCTURE" name="NOSE_2">
   <location unit="IN">
      <x> 296.220436 </x>
      <y> 0 </y>
      <z> -55.0271 </z>
   </location>
   <static_friction> 1.0 </static_friction>
   <dynamic_friction> 1.4 </dynamic_friction>
   <rolling_friction> 1.0 </rolling_friction>
   <spring_coeff unit="LBS/FT"> 1.5e+06 </spring_coeff>
   <damping_coeff unit="LBS/FT/SEC"> 50000 </damping_coeff>
   <max_steer unit="DEG"> 0.0 </max_steer>
   <brake_group> NONE </brake_group>
   <retractable>0</retractable>
   </contact>
   <contact type="STRUCTURE" name="CENTER_1">
   <location unit="IN">
      <x> 274.0157 </x>
      <y> 0 </y>
      <z> -60.0665 </z>
   </location>
   <static_friction> 1.0 </static_friction>
   <dynamic_friction> 1.4 </dynamic_friction>
   <rolling_friction> 1.0 </rolling_friction>
   <spring_coeff unit="LBS/FT"> 1.5e+06 </spring_coeff>
   <damping_coeff unit="LBS/FT/SEC"> 50000 </damping_coeff>
   <max_steer unit="DEG"> 0.0 </max_steer>
   <brake_group> NONE </brake_group>
   <retractable>0</retractable>
   </contact>
   <contact type="STRUCTURE" name="CENTER_2">
   <location unit="IN">
      <x> 930 </x>
      <y> 0 </y>
      <z> -60.0665 </z>
   </location>
   <static_friction> 1.0 </static_friction>
   <dynamic_friction> 1.4 </dynamic_friction>
   <rolling_friction> 1.0 </rolling_friction>
   <spring_coeff unit="LBS/FT"> 1.5e+06 </spring_coeff>
   <damping_coeff unit="LBS/FT/SEC"> 50000 </damping_coeff>
   <max_steer unit="DEG"> 0.0 </max_steer>
   <brake_group> NONE </brake_group>
   <retractable>0</retractable>
   </contact>
   <contact type="STRUCTURE" name="TAIL_1">
   <location unit="IN">
      <x> 992.87399 </x>
      <y> 0 </y>
      <z> -44.7722 </z>
   </location>
   <static_friction> 1.0 </static_friction>
   <dynamic_friction> 1.4 </dynamic_friction>
   <rolling_friction> 1.0 </rolling_friction>
   <spring_coeff unit="LBS/FT"> 1.5e+06 </spring_coeff>
   <damping_coeff unit="LBS/FT/SEC"> 50000 </damping_coeff>
   <max_steer unit="DEG"> 0.0 </max_steer>
   <brake_group> NONE </brake_group>
   <retractable>0</retractable>
   </contact>
   <contact type="STRUCTURE" name="TAIL_2">
   <location unit="IN">
      <x> 1119.88189 </x>
      <y> 0 </y>
      <z> -18.8067 </z>
   </location>
   <static_friction> 1.0 </static_friction>
   <dynamic_friction> 1.4 </dynamic_friction>
   <rolling_friction> 1.0 </rolling_friction>
   <spring_coeff unit="LBS/FT"> 1.5e+06 </spring_coeff>
   <damping_coeff unit="LBS/FT/SEC"> 50000 </damping_coeff>
   <max_steer unit="DEG"> 0.0 </max_steer>
   <brake_group> NONE </brake_group>
   <retractable>0</retractable>
   </contact>
   <contact type="STRUCTURE" name="TAIL_3">
   <location unit="IN">
      <x> 1236.49609 </x>
      <y> 0 </y>
      <z> -10.2599 </z>
   </location>
   <static_friction> 1.0 </static_friction>
   <dynamic_friction> 1.4 </dynamic_friction>
   <rolling_friction> 1.0 </rolling_friction>
   <spring_coeff unit="LBS/FT"> 1.5e+06 </spring_coeff>
   <damping_coeff unit="LBS/FT/SEC"> 50000 </damping_coeff>
   <max_steer unit="DEG"> 0.0 </max_steer>
   <brake_group> NONE </brake_group>
   <retractable>0</retractable>
   </contact>
   <contact type="STRUCTURE" name="TAIL_4">
   <location unit="IN">
      <x> 232.59841 </x>
      <y> 0 </y>
      <z> 47.4138 </z>
   </location>
   <static_friction> 1.0 </static_friction>
   <dynamic_friction> 1.4 </dynamic_friction>
   <rolling_friction> 1.0 </rolling_friction>
   <spring_coeff unit="LBS/FT"> 1.5e+06 </spring_coeff>
   <damping_coeff unit="LBS/FT/SEC"> 50000 </damping_coeff>
   <max_steer unit="DEG"> 0.0 </max_steer>
   <brake_group> NONE </brake_group>
   <retractable>0</retractable>
   </contact>
   <contact type="STRUCTURE" name="WING_TIP_1">
   <location unit="IN">
      <x> 838.8898 </x>
      <y> -667.5197 </y>
      <z> 35.7926 </z>
   </location>
   <static_friction> 1.0 </static_friction>
   <dynamic_friction> 1.4 </dynamic_friction>
   <rolling_friction> 1.0 </rolling_friction>
   <spring_coeff unit="LBS/FT"> 1.5e+06 </spring_coeff>
   <damping_coeff unit="LBS/FT/SEC"> 50000 </damping_coeff>
   <max_steer unit="DEG"> 0.0 </max_steer>
   <brake_group> NONE </brake_group>
   <retractable>0</retractable>
   </contact>
   <contact type="STRUCTURE" name="WING_TIP_2">
   <location unit="IN">
      <x> 838.8898 </x>
      <y> 667.5197 </y>
      <z> 35.7926 </z>
   </location>
   <static_friction> 1.0 </static_friction>
   <dynamic_friction> 1.4 </dynamic_friction>
   <rolling_friction> 1.0 </rolling_friction>
   <spring_coeff unit="LBS/FT"> 1.5e+06 </spring_coeff>
   <damping_coeff unit="LBS/FT/SEC"> 50000 </damping_coeff>
   <max_steer unit="DEG"> 0.0 </max_steer>
   <brake_group> NONE </brake_group>
   <retractable>0</retractable>
   </contact>
</ground_reactions>

<propulsion>
   <engine file="cfm56_5b3">
   <location unit="IN">
      <x> 589.735 </x>
      <y> -226.575 </y>
      <z> -45.567 </z>
   </location>
   <orient unit="DEG">
      <roll> 0.0 </roll>
      <pitch> 2.2 </pitch>
      <yaw> 1 </yaw>
   </orient>
   <feed>0</feed>
   <feed>1</feed>
   <feed>3</feed>
   <feed>4</feed>
   <feed>5</feed>
   <thruster file="direct">
      <location unit="IN">
      <x> 589.735 </x>
      <y> -226.575 </y>
      <z> -45.567 </z>
      </location>
      <orient unit="DEG">
      <roll> 0.0 </roll>
      <pitch> 2.2 </pitch>
      <yaw> 1 </yaw>
      </orient>
   </thruster>
   </engine>
   <engine file="cfm56_5b3">
   <location unit="IN">
      <x> 589.735 </x>
      <y> 226.575 </y>
      <z> -45.567 </z>
   </location>
   <orient unit="DEG">
      <roll> 0.0 </roll>
      <pitch> 2.2 </pitch>
      <yaw> -1 </yaw>
   </orient>
   <feed>0</feed>
   <feed>1</feed>
   <feed>3</feed>
   <feed>4</feed>
   <feed>5</feed>
   <thruster file="direct">
      <location unit="IN">
      <x> 589.735 </x>
      <y> 226.575 </y>
      <z> -45.567 </z>
      </location>
      <orient unit="DEG">
      <roll> 0.0 </roll>
      <pitch> 2.2 </pitch>
      <yaw> -1 </yaw>
      </orient>
   </thruster>
   </engine>
   <tank type="FUEL">    <!-- Left Tank (Inner) -->
      <location unit="IN">
         <x> 630.6588 </x>
         <y> -236.2992 </y>
         <z> -33.9470 </z>
      </location>
      <capacity unit="LBS"> 12186.9 </capacity>
      <contents unit="LBS"> 2437.38 </contents>
   </tank>
   <tank type="FUEL">    <!-- Left Tank (Outer) -->
      <location unit="IN">
         <x> 737.4190 </x>
         <y> -457.4259 </y>
         <z> -8.0898 </z>
      </location>
      <capacity unit="LBS"> 1548.8 </capacity>
      <contents unit="LBS"> 154.88 </contents>
   </tank>
   <tank type="FUEL">    <!-- Left Tank (Surge) -->
      <location unit="IN">
         <x> 788.4322 </x>
         <y> -574.4148 </y>
         <z> 3.1080 </z>
      </location>
      <capacity unit="LBS"> 328.13 </capacity>
      <contents unit="LBS"> 0 </contents>
   </tank>
   <tank type="FUEL">    <!-- Center Tank -->
      <location unit="IN">
         <x> 580.9955 </x>
         <y> 0 </y>
         <z> -47.0 </z>
      </location>
      <capacity unit="LBS"> 14520 </capacity>
      <contents unit="LBS"> 0 </contents>
   </tank>
   <tank type="FUEL">    <!-- Right Tank (Inner) -->
      <location unit="IN">
         <x> 630.6588 </x>
         <y> 236.2992 </y>
         <z> -33.9470 </z>
      </location>
      <capacity unit="LBS"> 12186.9 </capacity>
      <contents unit="LBS"> 2437.38 </contents>
   </tank>
   <tank type="FUEL">    <!-- Right Tank (Outer) -->
      <location unit="IN">
         <x> 737.4190 </x>
         <y> 457.4259 </y>
         <z> -8.0898 </z>
      </location>
      <capacity unit="LBS"> 1548.8 </capacity>
      <contents unit="LBS"> 154.88 </contents>
   </tank>
   <tank type="FUEL">    <!-- Right Tank (Surge) -->
      <location unit="IN">
         <x> 788.4322 </x>
         <y> 574.4148 </y>
         <z> 3.1080 </z>
      </location>
      <capacity unit="LBS"> 328.13 </capacity>
      <contents unit="LBS"> 0 </contents>
   </tank>
</propulsion>

<system file="pushback" />

<flight_control name="FCS: A320">
   <channel name="Pitch">
   <summer name="Pitch Trim Sum">
      <input>fcs/elevator-cmd-norm</input>
      <input>fcs/pitch-trim-cmd-norm</input>
      <clipto>
      <min>-1</min>
      <max>1</max>
      </clipto>
   </summer>

   <aerosurface_scale name="Elevator Control">
      <input>fcs/pitch-trim-sum</input>
      <range>
      <min>-18</min>
      <max>11</max>
      </range>
      <output>fcs/elevator-pos-rad</output>
   </aerosurface_scale>

   <aerosurface_scale name="Elevator position normalized">
      <input>fcs/elevator-pos-deg</input>
      <domain>
      <min>-18</min>
      <max>11</max>
      </domain>
      <range>
      <min>-1</min>
      <max>1</max>
      </range>
      <output>fcs/elevator-pos-norm</output>
   </aerosurface_scale>
   </channel>
   <channel name="Roll">
   <summer name="Roll Trim Sum">
      <input>fcs/aileron-cmd-norm</input>
      <input>fcs/roll-trim-cmd-norm</input>
      <clipto>
      <min>-1</min>
      <max>1</max>
      </clipto>
   </summer>

   <aerosurface_scale name="Left Aileron Control">
      <input>fcs/roll-trim-sum</input>
      <gain>0.02</gain>
      <range>
      <min>-25</min>
      <max>25</max>
      </range>
      <output>fcs/left-aileron-pos-rad</output>
   </aerosurface_scale>

   <aerosurface_scale name="Right Aileron Control">
      <input>-fcs/roll-trim-sum</input>
      <gain>0.02</gain>
      <range>
      <min>-25</min>
      <max>25</max>
      </range>
      <output>fcs/right-aileron-pos-rad</output>
   </aerosurface_scale>

   <aerosurface_scale name="Left Aileron position normalized">
      <input>fcs/left-aileron-pos-deg</input>
      <domain>
      <min>-25</min>
      <max>25</max>
      </domain>
      <range>
      <min>-0.75</min>
      <max>1</max>
      </range>
      <output>fcs/left-aileron-pos-norm</output>
   </aerosurface_scale>

   <aerosurface_scale name="Right Aileron position normalized">
      <input>fcs/right-aileron-pos-deg</input>
      <domain>
      <min>-25</min>
      <max>25</max>
      </domain>
      <range>
      <min>-0.75</min>
      <max>1</max>
      </range>
      <output>fcs/right-aileron-pos-norm</output>
   </aerosurface_scale>
   </channel>
   <channel name="Yaw">
   <pure_gain name="Yaw Damper Rate">
      <input>velocities/r-rad_sec</input>
      <gain>2</gain>
   </pure_gain>

   <pure_gain name="Yaw Damper Beta">
      <input>aero/beta-rad</input>
      <gain>-5</gain>
   </pure_gain>

   <summer name="Yaw Trim Sum">
      <input>fcs/rudder-cmd-norm</input>
      <input>fcs/yaw-trim-cmd-norm</input>
      <clipto>
      <min>-1</min>
      <max>1</max>
      </clipto>
   </summer>

   <summer name="Rudder Sum">
      <input>fcs/yaw-trim-sum</input>
      <input>fcs/yaw-damper-rate</input>
      <input>fcs/yaw-damper-beta</input>
      <clipto>
      <min>-1</min>
      <max>1</max>
      </clipto>
   </summer>

   <aerosurface_scale name="Rudder Control">
      <input>fcs/rudder-sum</input>
      <gain>0.01745</gain>
      <range>
      <min>-25</min>
      <max>25</max>
      </range>
      <output>fcs/rudder-pos-rad</output>
   </aerosurface_scale>

   <aerosurface_scale name="Rudder position normalized">
      <input>fcs/rudder-pos-deg</input>
      <domain>
      <min>-25</min>
      <max>25</max>
      </domain>
      <range>
      <min>-1</min>
      <max>1</max>
      </range>
      <output>fcs/rudder-pos-norm</output>
   </aerosurface_scale>
   </channel>
   <channel name="Flaps">
   <kinematic name="Flaps Control">
      <input>fcs/flap-cmd-norm</input>
      <traverse>
      <setting>
         <position>0</position>
         <time>0</time>
      </setting>
      <setting>
         <position>40</position>
         <time>40</time>
      </setting>
      </traverse>
      <output>fcs/flap-pos-deg</output>
   </kinematic>

   <aerosurface_scale name="Flap position normalized">
      <input>fcs/flap-pos-deg</input>
      <domain>
      <min>0</min>
      <max>40</max>
      </domain>
      <range>
      <min>0</min>
      <max>1</max>
      </range>
      <output>fcs/flap-pos-norm</output>
   </aerosurface_scale>
   </channel>
   <channel name="Landing Gear">
   <kinematic name="Gear Control">
      <input>gear/gear-cmd-norm</input>
      <traverse>
      <setting>
         <position>0</position>
         <time>0</time>
      </setting>
      <setting>
         <position>1</position>
         <time>10</time>
      </setting>
      </traverse>
      <output>gear/gear-pos-norm</output>
   </kinematic>
   </channel>
   <channel name="Speedbrake">
   <kinematic name="Speedbrake">
      <input>fcs/speedbrake-cmd-norm</input>
      <traverse>
      <setting>
         <position>0</position>
         <time>0</time>
      </setting>
      <setting>
         <position>1</position>
         <time>2</time>
      </setting>
      </traverse>
      <output>fcs/speedbrake-pos-norm</output>
   </kinematic>
   </channel>
</flight_control>
<aerodynamics>

   <axis name="DRAG">
   <function name="aero/coefficient/CDo">
      <description>Drag_at_zero_lift</description>
      <product>
      <property>aero/qbar-psf</property>
      <property>metrics/Sw-sqft</property>
      <value>0.014</value>
      </product>
   </function>
   <function name="aero/coefficient/CDalpha">
      <description>Drag_due_to_alpha</description>
      <product>
      <property>aero/qbar-psf</property>
      <property>metrics/Sw-sqft</property>
      <table>
         <independentVar lookup="row">aero/alpha-rad</independentVar>
         <independentVar lookup="column">fcs/flap-pos-deg</independentVar>
         <tableData>
            0.0000   1.0000   25.0000   40.0000
         -0.0873   0.0041   0.0000   0.0005   0.0014
         -0.0698   0.0013   0.0004   0.0025   0.0041
         -0.0524   0.0001   0.0023   0.0059   0.0084
         -0.0349   0.0003   0.0057   0.0108   0.0141
         -0.0175   0.0020   0.0105   0.0172   0.0212
         0.0000   0.0052   0.0168   0.0251   0.0399
         0.0175   0.0099   0.0248   0.0346   0.0502
         0.0349   0.0162   0.0342   0.0457   0.0621
         0.0524   0.0240   0.0452   0.0583   0.0755
         0.0698   0.0334   0.0577   0.0724   0.0904
         0.0873   0.0442   0.0718   0.0881   0.1068
         0.1047   0.0566   0.0874   0.1053   0.1248
         0.1222   0.0706   0.1045   0.1240   0.1443
         0.1396   0.0860   0.1232   0.1442   0.1654
         0.1571   0.0962   0.1353   0.1573   0.1790
         0.1745   0.1069   0.1479   0.1708   0.1930
         0.1920   0.1180   0.1610   0.1849   0.2075
         0.2094   0.1298   0.1746   0.1995   0.2226
         0.2269   0.1424   0.1892   0.2151   0.2386
         0.2443   0.1565   0.2054   0.2323   0.2564
         0.2618   0.1727   0.2240   0.2521   0.2767
         0.2793   0.1782   0.2302   0.2587   0.2835
         0.2967   0.1716   0.2227   0.2507   0.2753
         0.3142   0.1618   0.2115   0.2388   0.2631
         0.3316   0.1475   0.1951   0.2214   0.2451
         0.3491   0.1097   0.1512   0.1744   0.1966
         </tableData>
      </table>
      </product>
   </function>
   <function name="aero/coefficient/CDde">
      <description>Drag_due_to_elevator_Deflection</description>
      <product>
      <property>aero/qbar-psf</property>
      <property>metrics/Sw-sqft</property>
      <property>fcs/mag-elevator-pos-rad</property>
      <value>0.0900</value>
      </product>
   </function>
   <function name="aero/coefficient/CDbeta">
      <description>Drag_due_to_sideslip</description>
      <product>
      <property>aero/qbar-psf</property>
      <property>metrics/Sw-sqft</property>
      <property>aero/mag-beta-rad</property>
      <value>0.5000</value>
      </product>
   </function>
   <function name="aero/coefficient/CDgear">
      <description>Drag_due_to_landing_gear</description>
      <product>
      <property>aero/qbar-psf</property>
      <property>metrics/Sw-sqft</property>
      <property>gear/gear-pos-norm</property>
      <value>0.0400</value>
      </product>
   </function>
   <function name="aero/coefficient/CDspeedbrake">
      <description>Drag_due_to_speedbrake</description>
      <product>
      <property>aero/qbar-psf</property>
      <property>metrics/Sw-sqft</property>
      <property>fcs/speedbrake-pos-norm</property>
      <value>0.0400</value>
      </product>
   </function>
   </axis>

   <axis name="SIDE">
   <function name="aero/coefficient/CYb">
      <description>Side_force_due_to_beta</description>
      <product>
      <property>aero/qbar-psf</property>
      <property>metrics/Sw-sqft</property>
      <table>
         <independentVar>aero/beta-rad</independentVar>
         <tableData>
         -0.3500   0.5000
         0.0000   0.0000
         0.3500   -0.5000
         </tableData>
      </table>
      </product>
   </function>
   </axis>

   <axis name="LIFT">
   <function name="aero/coefficient/CLalpha">
      <description>Lift_due_to_alpha</description>
      <product>
      <property>aero/qbar-psf</property>
      <property>metrics/Sw-sqft</property>
      <table>
         <independentVar lookup="row">aero/alpha-rad</independentVar>
         <independentVar lookup="column">fcs/flap-pos-deg</independentVar>
         <tableData>
            0.0000   1.0000   9.0000   10.0000   40.0000
         -0.0900   -0.2200   -0.2200   -0.1200   -0.1200   0.3200
         0.0000   0.2500   0.2500   0.3500   0.3500   0.7500
         0.0900   0.7300   0.7300   0.8300   0.8300   1.2300
         0.1000   0.8300   0.8300   0.9300   0.9300   1.3300
         0.1200   0.9200   0.9200   1.0200   1.0200   1.4200
         0.1400   1.0200   1.0200   1.1200   1.1200   1.5200
         0.1600   1.0800   1.0800   1.1800   1.1800   1.5800
         0.1700   1.1300   1.1300   1.2300   1.2300   1.6300
         0.1900   1.1900   1.1900   1.2900   1.2900   1.6900
         0.2100   1.2500   1.2500   1.3500   1.3500   1.7700
         0.2400   1.3500   1.3700   1.4700   1.4800   1.9300
         0.2600   1.4400   1.4700   1.5700   1.6200   2.1200
         0.2800   1.4700   1.5100   1.6100   1.7800   2.4000
         0.3000   1.5000   1.5600   1.6600   1.9000   2.3000
         0.3200   1.4700   1.6100   1.6000   1.7000   2.0300
         0.3400   1.3500   1.5000   1.4100   1.5000   1.5300
         0.3600   1.1500   1.2000   1.2000   1.2000   1.2000
         </tableData>
      </table>
      </product>
   </function>
   <function name="aero/coefficient/CLDe">
      <description>Lift_due_to_Elevator_Deflection</description>
      <product>
      <property>aero/qbar-psf</property>
      <property>metrics/Sw-sqft</property>
      <property>fcs/elevator-pos-rad</property>
      <value>0.1930</value>
      </product>
   </function>
   </axis>

   <axis name="ROLL">
   <function name="aero/coefficient/Clb">
      <description>Roll_moment_due_to_beta</description>
      <product>
      <property>aero/qbar-psf</property>
      <property>metrics/Sw-sqft</property>
      <property>metrics/bw-ft</property>
      <table>
         <independentVar>aero/beta-rad</independentVar>
         <tableData>
         -0.3500   0.0100
         0.0000   0.0000
         0.3500   -0.0100
         </tableData>
      </table>
      </product>
   </function>
   <function name="aero/coefficient/Clp">
      <description>Roll_moment_due_to_roll_rate_(roll_damping)</description>
      <product>
      <property>aero/qbar-psf</property>
      <property>metrics/Sw-sqft</property>
      <property>metrics/bw-ft</property>
      <property>aero/bi2vel</property>
      <property>velocities/p-aero-rad_sec</property>
      <value>-0.5000</value>
      </product>
   </function>
   <function name="aero/coefficient/Clr">
      <description>Roll_moment_due_to_yaw_rate</description>
      <product>
      <property>aero/qbar-psf</property>
      <property>metrics/Sw-sqft</property>
      <property>metrics/bw-ft</property>
      <property>aero/bi2vel</property>
      <property>velocities/r-aero-rad_sec</property>
      <value>0.0050</value>
      </product>
   </function>
   <function name="aero/coefficient/Clda">
      <description>Roll_moment_due_to_aileron</description>
      <product>
      <property>aero/qbar-psf</property>
      <property>metrics/Sw-sqft</property>
      <property>metrics/bw-ft</property>
      <property>fcs/left-aileron-pos-rad</property>
      <value>0.2000</value>
      </product>
   </function>
   <function name="aero/coefficient/Cldr">
      <description>Roll_moment_due_to_rudder</description>
      <product>
      <property>aero/qbar-psf</property>
      <property>metrics/Sw-sqft</property>
      <property>metrics/bw-ft</property>
      <property>fcs/rudder-pos-rad</property>
      <value>0.0050</value>
      </product>
   </function>
   </axis>

   <axis name="PITCH">
   <function name="aero/coefficient/Cmo">
      <description>Pitching_moment_at_zero_alpha</description>
      <product>
      <property>aero/qbar-psf</property>
      <property>metrics/Sw-sqft</property>
      <property>metrics/cbarw-ft</property>
      <table>
         <independentVar>fcs/flap-pos-deg</independentVar>
         <tableData>
         0.0000   0.0400
         40.0000   -0.1000
         </tableData>
      </table>
      </product>
   </function>
   <function name="aero/coefficient/Cmalpha">
      <description>Pitch_moment_due_to_alpha</description>
      <product>
      <property>aero/qbar-psf</property>
      <property>metrics/Sw-sqft</property>
      <property>metrics/cbarw-ft</property>
      <property>aero/alpha-rad</property>
      <value>-4.0000</value>
      </product>
   </function>
   <function name="aero/coefficient/CmDe">
      <description>Pitch_moment_due_to_elevator_Deflection</description>
      <product>
      <property>aero/qbar-psf</property>
      <property>metrics/Sw-sqft</property>
      <property>metrics/cbarw-ft</property>
      <property>fcs/elevator-pos-rad</property>
      <value>-1.5000</value>
      </product>
   </function>
   <function name="aero/coefficient/Cmq">
      <description>Pitch_moment_due_to_pitch_rate</description>
      <product>
      <property>aero/qbar-psf</property>
      <property>metrics/Sw-sqft</property>
      <property>metrics/cbarw-ft</property>
      <property>aero/ci2vel</property>
      <property>velocities/q-aero-rad_sec</property>
      <value>-10.0000</value>
      </product>
   </function>
   <function name="aero/coefficient/Cmadot">
      <description>Pitch_moment_due_to_alpha_rate</description>
      <product>
      <property>aero/qbar-psf</property>
      <property>metrics/Sw-sqft</property>
      <property>metrics/cbarw-ft</property>
      <property>aero/ci2vel</property>
      <property>aero/alphadot-rad_sec</property>
      <value>-12.0000</value>
      </product>
   </function>
   </axis>

   <axis name="YAW">
   <function name="aero/coefficient/Cnr">
      <description>Yaw_moment_due_to_yaw_rate</description>
      <product>
      <property>aero/qbar-psf</property>
      <property>metrics/Sw-sqft</property>
      <property>metrics/bw-ft</property>
      <property>aero/bi2vel</property>
      <property>velocities/r-aero-rad_sec</property>
      <value>-0.0400</value>
      </product>
   </function>
   <function name="aero/coefficient/Cnb">
      <description>Yaw_moment_due_to_beta</description>
      <product>
      <property>aero/qbar-psf</property>
      <property>metrics/Sw-sqft</property>
      <property>metrics/bw-ft</property>
      <property>aero/beta-rad</property>
      <value>0.2000</value>
      </product>
   </function>
   <function name="aero/coefficient/Cndr">
      <description>Yaw_moment_due_to_rudder</description>
      <product>
      <property>aero/qbar-psf</property>
      <property>metrics/Sw-sqft</property>
      <property>metrics/bw-ft</property>
      <property>fcs/rudder-pos-rad</property>
      <value>-0.5000</value>
      </product>
   </function>
   </axis>
</aerodynamics>

   <external_reactions>
      <force name="pushback" frame="BODY">
         <location unit="IN">
            <x>294</x>
            <y>0</y>
            <z>-149</z>
         </location>
         <direction>
            <x>1</x>
            <y>0</y>
            <z>0</z>
         </direction>
      </force>
   </external_reactions>
</fdm_config>


So ,any idea where the problems is?

Flaps,today with wing fuel tanks full,40% in the central tank,about 50% of the PAX and Cargo weight,flaps on 3,but still ,the aircraft needed more then the rw is long and it took at about 220 kts. So,I will either screw this completely or find some way to fix,with the help of all of you here.

Cheers.
FGRS
 
Posts: 96
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Re: Airbus A320 [Family]

Postby daveculp » Fri Feb 07, 2014 2:25 am

Did the airplane not rotate? Did it stay on the runway even after rotation?
User avatar
daveculp
 
Posts: 503
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Location: Las Vegas, USA
Callsign: DCulp
Version: 2017.3.1
OS: Ubuntu 17.10

Re: Airbus A320 [Family]

Postby FGRS » Fri Feb 07, 2014 8:59 am

The A320 Family ,developed by Skyop ,when running on my FG which is 2.8 and on my PC configuration,had a huge pitch problems. It was quite fine on take off,even when properly loaded with fuel and PAX. But as soon as the AP is on,the aircraft was making a very annoying and if progresses ,catastrophic pitch/dive movement. There is no stabilizing,you can't stop that ....nothing. The plane just goes on and on with that,until it stalls .

So I after some tinkering,I was able to eliminate that behavior ,but now the problem is that the aircraft (all of them ) need way too much rw for take off. Last night I was testing the A321-200 ,and in went way out of the rw to take off. The rw length is more then enough for it to take off,but it didn't. And even if it do take off,on 250KIAS it's barely climbing.

In my previous post is the xml file of that aircraft,since his behavior is by far the worst. A320-200 is a little bit better,but I still have to test it with a full load,as well as the others (A318,A319)

So,any idea?

Thanks everyone.

Cheers
FGRS
 
Posts: 96
Joined: Sat Nov 02, 2013 3:04 pm
Location: LQBK
Callsign: UAV001
Version: 2.8
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Re: Airbus A320 [Family]

Postby Honzaku » Fri Feb 07, 2014 9:26 am

Hi,

few hints for you. I don't know exactly this ACF and your problem but I bet it is surely one of the two things:

    Insufficient lift due to either wrong lift coeff. vs. AOA curve or wrong (small) wing area.
    Wrong total pitch moment management within your model.

If the excessive AOA or excessive speed must be maintained to keep the plane in horizontal flight as well as if the plane rotates correctly during T/O but doesn't airborn until the speed is excessively high it means the first problem of the two.

If the plane doesn't want even to rotate until the speed is excessively high, or if it is hard or even impossible maintain desired (normal) attitude during the flight, it would be probably the latter one since the pitch moment is likely to be badly calculated because of many reasons.
The most probable causes are: wrong COG position (I mean actual COG position of the ACF with fuel and PAX, not that one which is written in the .xml file, that is just empty ACF), badly chosen position of Aero RP, wrong basic pitch moment coefficient due to AOA curve, insufficient authority of the elevator - in other words too small pitch moment due to elevator deflection coefficient, or more likely combination of two or more of the these causes.

Of course it can be the combination of both - insufficient lift and wrong pitch moment.

Cheers

Honza
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Re: Airbus A320 [Family]

Postby FGRS » Fri Feb 07, 2014 10:45 am

Thanks Honzaku very much. I'm not a developer of the aircraft,that's Skyop,which I'm tying to contact for years because of this AC.

Since that,and the fact that I just learning this whole thing,the best help would be to quite simply,point out ,where in the xml. of this aircraft is this problem. What to change? Is it possible to use some data from A320Neo since both aircraft are using the same FDM,the jsb?

Edit: After more testing,it's obvious that A321 is in a very bad shape. Others,A318/ 319/ 320 are more than ok. Even when almost fully loaded,all of them can take off at about 180-190 kts ,and the climb out is beautiful,with no problems. So,with the other aircraft ruled out,we can now switch all attention to the A321-200,to somehow fix it.

Does anyone here know,which aircraft ,beside the A320 both this and Neo,are using the JsbSim?

Thanks.
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Re: Airbus A320 [Family]

Postby HelldiverSquadron » Fri Feb 07, 2014 6:29 pm

Hm...yeah, I have a pitch issue when fully loaded around 200kts. it climbs fine but after it reaches 190-200 it looks like a tcas issue its that bad :P
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Re: Airbus A320 [Family]

Postby FGRS » Fri Feb 07, 2014 8:49 pm

That's what I'm talking about. In my case,that's even worse,but not on all of the A320s ,just A321. For other,I have managed to solve that...sort of. There are still some problems ,but I guess I will solve them somehow. I will say again,anyone willing to help to fix these planes,is more then welcome.

Cheers
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Re: Airbus A320 [Family]

Postby HelldiverSquadron » Sat Feb 08, 2014 1:18 am

im no coder, so anyone be my guest. its a great aeroplane, though
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Re: Airbus A320 [Family]

Postby KL-666 » Sat Feb 08, 2014 1:42 am

Hi,

I see there is a lot of activity around the a-family. In another context i did a little flight test. Maybe the conclusions can help you point at the issues.

http://forum.flightgear.org/viewtopic.php?f=49&t=21780&start=150#p198681

Kind regards, Vincent
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Re: Airbus A320 [Family]

Postby FGRS » Mon Feb 17, 2014 9:07 pm

So,

After more testing,coding etc..The verdict about the A320 Family is this.

There are two main problems. Pitch and flaps. In one of my previous posts,I said that ,with the pitch problems solved (crazy pitch dive behavior) ,the aircraft needed way to much speed and runway to take off. With some changes in the FDM,I have managed to make a nice take off at a normal speed,with almost fully loaded aircraft,on the rw of my home airport,which is 2500m long.

The solution was to change some parameters regarding Lift,more precisely,lift due to flaps,which was close to none. In fact I had to write one more function in the section of aerodynamics . With the flaps retracted,and still on manual flying,the aircraft started to pitch down,not dangerous but it reveals the last and I think ,the main problem,the lift ability of the wings.

I would like to see some ideas and answers ,how to solve that,without creating even more problems.

Cheers

BTW ,the test aircraft was the A320-211 CFM 56 version.
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Re: Airbus A320 [Family]

Postby daveculp » Tue Feb 18, 2014 7:38 pm

First thing to try is setting the takeoff trim. Right now it's set to zero. It needs to be about -0.2. It takes off fine.
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