Merge pull request #472 from HHS81/Issue463-FlapsDamage-2

Implement Flap damage due to overspeed
HHS81 · Dec 22, 2021 · dc84700 · dc84700
2 parents a5e7e6e + 7780dd8
commit dc84700
Show file tree

Hide file tree

Showing 7 changed files with 108 additions and 30 deletions.
diff --git a/Nasal/damage.nas b/Nasal/damage.nas
@@ -71,7 +71,9 @@ setlistener("/sim/signals/fdm-initialized", func {
         {id:"/fdm/jsbsim/gear/unit[2]/broken",    name:"Right main gear"},
 
         {id:"/fdm/jsbsim/wing-damage/left-wing",  name:"Left wing"},
-        {id:"/fdm/jsbsim/wing-damage/right-wing", name:"Right wing"}
+        {id:"/fdm/jsbsim/wing-damage/right-wing", name:"Right wing"},
+
+        {id:"/fdm/jsbsim/wing-damage/flaps",  name:"Flaps"}
     ];
 
     var dmgdelayInit = 0.15; # delay in seconds; should be before init of aircraft states (it might repair the plane)

diff --git a/Systems/damage.xml b/Systems/damage.xml
@@ -181,6 +181,43 @@
             <gain>3.8</gain> <!-- 3.8 g's -->
         </pure_gain>
 
+        <!-- Flaps stuck means the actuar push rod was bent due to overstress, preventing further movement.
+             Note: According to our research (see https://github.com/HHS81/c182s/issues/463), this is the
+                   most probable cause of flap problem caused by flying error. Especially a rip off of the rod,
+                   which causes loose flap (ie. instant 0° flaps) is very uncommon and thus not modelled here.
+                   Also, a loose flap is usually caused by corrosion of the connecting rod between the two flaps,
+                   which is caused by wrong or lack of maintenance. This may be modelled in the future.
+        -->
+        <fcs_function name="damage/limits-flaps-stuck">
+          <function>
+                <product>
+                    <table>
+                        <independentVar lookup="row">fcs/flap-pos-deg</independentVar>
+                        <tableData breakPoint="0">
+                            <!-- limits for flapDeg to KIAS, from POH 2-4, +sqrt(1.5) (KIAS: 10°=140, 20°=120, full=100) -->
+                             0   999
+                            10   175
+                            20   147
+                            38   122
+                        </tableData>
+                    </table>
+                    <difference>
+                        <value>1.0</value>
+                        <table>
+                            <!-- reduce speed limits depending on roll factor -->
+                            <independentVar lookup="row">damage/roll-moment</independentVar>
+                            <tableData breakPoint="0">
+                               -8000  0.20
+                                -2000  0.00
+                                 2000  0.00
+                                8000  0.20
+                            </tableData>
+                        </table>
+                    </difference>
+                </product>
+          </function>
+        </fcs_function>
+
         <pure_gain name="damage/force-aero-lbs">
             <input>forces/fbz-aero-lbs</input>
             <gain>-1.0</gain>
@@ -387,7 +424,33 @@
                 wing-damage/right-wing LT 0.085
             </test>
         </switch>
+
+
+
+        <!-- Flaps damage -->
+        <switch name="flaps-damage">
+            <output>wing-damage/flaps</output>
+            <default value="wing-damage/flaps"/>
+
+            <!-- restore saved damage on sim startup -->
+            <test logic="AND" value="wing-damage/flaps-saved">
+                /sim/time/elapsed-sec LT 0.25
+                wing-damage/flaps-saved GT 0
+            </test>
 
+            <!-- Reset to no damage when repairing -->
+            <test logic="OR" value="0.0">
+                settings/damage EQ 0
+                damage/repairing EQ 1
+            </test>
+
+            <!-- Overspeed -->
+            <test logic="AND" value="0.25">
+                /velocities/airspeed-kt GT damage/limits-flaps-stuck
+                wing-damage/flaps LT 0.25
+            </test>
+        </switch>
+
     </channel>
 
     <channel name="upside-down">

diff --git a/c182s-set.xml b/c182s-set.xml
@@ -945,6 +945,7 @@
             <path>/fdm/jsbsim/gear/unit[2]/broken-saved</path> <!-- right main gear -->
             <path>/fdm/jsbsim/wing-damage/left-wing-saved</path>
             <path>/fdm/jsbsim/wing-damage/right-wing-saved</path>
+            <path>/fdm/jsbsim/wing-damage/flaps-saved</path>
 
             <path>/fdm/jsbsim/systems/propulsion/sparkplugs/left/fouling-savedrestore</path>
             <path>/fdm/jsbsim/systems/propulsion/sparkplugs/right/fouling-savedrestore</path>
@@ -1361,18 +1362,7 @@
  </payload>
 
  <limits>
-   <max-flap-extension-speed>
-     <flaps>0.26315</flaps>
-     <speed>140</speed>
-   </max-flap-extension-speed>
-   <max-flap-extension-speed>
-     <flaps>0.52</flaps>
-     <speed>120</speed>
-   </max-flap-extension-speed>
-   <max-flap-extension-speed>
-     <flaps>1.0</flaps>
-     <speed>100</speed>
-   </max-flap-extension-speed>
+   <!-- Flap extension limits: in damage.xml -->
    <max-positive-g>3.5</max-positive-g>
    <max-negative-g>-1.52</max-negative-g>
    <vne>175</vne>

diff --git a/c182s-sound.xml b/c182s-sound.xml
@@ -274,7 +274,6 @@
         </crash>
 
 
-
  <squeal1>
    <name>squeal1</name>
       <path>Sounds/touchdown-screach2.wav</path>

diff --git a/c182s.xml b/c182s.xml
@@ -979,6 +979,11 @@
                 <test logic="AND" value="fcs/flap-pos-norm">
                     /systems/electrical/outputs/flaps le 16
                 </test>
+
+                <!-- make flaps stuck when overspeed damage occured -->
+                <test logic="OR" value="fcs/flap-pos-norm">
+                    wing-damage/flaps GE 0.25
+                </test>
             </switch>
             <kinematic name="Flaps Control">
                 <input>fcs/flap-input-norm</input>
@@ -1003,8 +1008,19 @@
                 <output>fcs/flap-pos-norm</output>
             </kinematic>
 
+        <!-- select flaps command source -->
+        <switch name="Flaps Command selector">
+            <output>fcs/flap-input-norm-selected</output>
+            <default value="fcs/flap-pos-norm"/>
+
+            <!-- flaps rod breakage: instantly 0° -->
+            <test logic="OR" value="0">
+                wing-damage/flaps EQ 1.00
+            </test>
+        </switch>
+
 	<aerosurface_scale name="Flap Position Normalizer">
-              <input>fcs/flap-pos-norm</input>
+              <input>fcs/flap-input-norm-selected</input>
               <domain>
                 <min>0</min>  
                 <max>1</max> 
@@ -1325,7 +1341,6 @@
                     <value>3.9</value>
                 </product>
             </function>
-        </axis>
 
 <!--taken from SenecaII by Torsten Dreyer-->
            <function name="aero/coefficient/CLicew">
@@ -1344,6 +1359,9 @@
                 </product>
             </function>
 
+    </axis>
+
+
         <axis name="DRAG">
             <function name="aero/coefficient/CDo">
                 <description>Drag_at_zero_lift</description>

diff --git a/c182t-set.xml b/c182t-set.xml
@@ -861,6 +861,7 @@
             <path>/fdm/jsbsim/gear/unit[2]/broken-saved</path> <!-- right main gear -->
             <path>/fdm/jsbsim/wing-damage/left-wing-saved</path>
             <path>/fdm/jsbsim/wing-damage/right-wing-saved</path>
+            <path>/fdm/jsbsim/wing-damage/flaps-saved</path>
 
             <path>/consumables/fuel/tank[0]/level-gal_us</path>
             <path>/consumables/fuel/tank[1]/level-gal_us</path>
@@ -1260,18 +1261,7 @@
  </payload>
 
  <limits>
-   <max-flap-extension-speed>
-     <flaps>0.26315</flaps>
-     <speed>140</speed>
-   </max-flap-extension-speed>
-   <max-flap-extension-speed>
-     <flaps>0.52</flaps>
-     <speed>120</speed>
-   </max-flap-extension-speed>
-   <max-flap-extension-speed>
-     <flaps>1.0</flaps>
-     <speed>100</speed>
-   </max-flap-extension-speed>
+   <!-- Flap extension limits: in damage.xml -->
    <max-positive-g>3.5</max-positive-g>
    <max-negative-g>-1.52</max-negative-g>
    <vne>175</vne>

diff --git a/c182t.xml b/c182t.xml
@@ -979,6 +979,11 @@
                 <test logic="AND" value="fcs/flap-pos-norm">
                     /systems/electrical/outputs/flaps le 16
                 </test>
+
+                <!-- make flaps stuck when overspeed damage occured -->
+                <test logic="OR" value="fcs/flap-pos-norm">
+                    wing-damage/flaps GE 0.25
+                </test>
             </switch>
             <kinematic name="Flaps Control">
                 <input>fcs/flap-input-norm</input>
@@ -1003,8 +1008,18 @@
                 <output>fcs/flap-pos-norm</output>
             </kinematic>
 
+        <!-- select flaps command source -->
+        <switch name="Flaps Command selector">
+            <output>fcs/flap-input-norm-selected</output>
+            <default value="fcs/flap-pos-norm"/>
+
+            <!-- flaps rod breakage: instantly 0° -->
+            <test logic="OR" value="0">
+                wing-damage/flaps EQ 1.00
+            </test>
+        </switch>
 	<aerosurface_scale name="Flap Position Normalizer">
-              <input>fcs/flap-pos-norm</input>
+              <input>fcs/flap-input-norm-selected</input>
               <domain>
                 <min>0</min>  
                 <max>1</max> 
@@ -1326,7 +1341,6 @@
                     <value>3.9</value>
                 </product>
             </function>
-        </axis>
 
 <!--taken from SenecaII by Torsten Dreyer-->
            <function name="aero/coefficient/CLicew">
@@ -1345,6 +1359,8 @@
                 </product>
             </function>
 
+        </axis>
+
         <axis name="DRAG">
             <function name="aero/coefficient/CDo">
                 <description>Drag_at_zero_lift</description>