From 9b1e230b87efc9a90e7cb7251e2230ef93c39a51 Mon Sep 17 00:00:00 2001
From: curt <curt>
Date: Wed, 4 Jun 2003 17:54:08 +0000
Subject: [PATCH] Lee Elliott:

I've been messing with the yf23 some more.  I think it flies a bit better now
and has more reasonable auto-pilot take-off characteristics - just apply full
power and go, and it doesn't go into such a steep climb.

Out of curiosity, I've also taken the rudder control input and linked it to
the stabilators/elevators and ailerons.  Now, with some slick joystick
manipulation it's possible to fly it at about 30 deg off-axis in more or less
level flight (actually, with full 'rudder' input, it looks nearer to 40 deg
to me and you end up tracing a very long curve).

If no rudder input is used it flies 'normally'.

I'd like to be able to 'tune' it so that it's more stable while transitioning
but I'm not sure if that's going to be possible.  It's also high-lighted some
problems I'm having with my Sidewinder joystick - when I use the rudder
control, the engine No.2 throttle jumps to 50% unless auto-throttle is
engaged (this also happens with the b52 too), and there seems to be some
interaction between the different axis if all three (roll, pitch and rudder)
are changed at the same time - difficult to be sure on that one though.

I'll probably un-map the throttle control from the joystick as I tend to use
the keyboard for engine control anyway, especially for landing.
---
 Aircraft-yasim/yf23-yasim.xml | 53 +++++++++++++++++++----------------
 Aircraft/yf23-yasim-set.xml   | 12 ++++----
 2 files changed, 35 insertions(+), 30 deletions(-)

diff --git a/Aircraft-yasim/yf23-yasim.xml b/Aircraft-yasim/yf23-yasim.xml
index 515fe72f1..ba157a47c 100644
--- a/Aircraft-yasim/yf23-yasim.xml
+++ b/Aircraft-yasim/yf23-yasim.xml
@@ -38,9 +38,7 @@
  <cockpit x="5.70" y="0.00" z="1.26"/>
 
 <!-- Fuselage entries for the fuselage proper and the two
-     engine housings.  The YF23 is basically a wing with
-     these three fuselage/housings, and the elevator.  For
-     this reason I've started the wings from the center-line.
+     engine housings.
 -->
 <!-- Fuselage -->
  <fuselage ax="10.00" ay="0.00" az="0.00"
@@ -48,38 +46,41 @@
           width="1.6" taper="0.5" midpoint="0.5"/>
 
 <!-- Left engine housing -->
-
  <fuselage ax="-2.00" ay="1.80" az="0.00"
           bx="-8.00" by="1.20" bz="0.60"
           width="1.2" taper="0" midpoint="0.3"/>
 
 <!-- Right engine housing -->
-
  <fuselage ax="-2.00" ay="-1.80" az="0.00"
           bx="-8.00" by="-1.20" bz="0.60"
           width="1.2" taper="0" midpoint="0.3"/>
 
-<!-- GW stall characteristics -->
-<!--
+<!-- Lots of guesswork here -->
  <wing x="-2.00" y="0.00" z="0.25" length="6.66" chord="12.00"
-      taper="0.08" sweep="0" dihedral="0" camber="0" incidence="-0.4">
-  <stall aoa="35" width="3" peak="1.3"/>
-  <flap0 start="0.36" end="0.63" lift="1.1" drag="1.8"/>
-  <flap1 start="0.63" end="0.89" lift="1.1" drag="1.3"/>
+      taper="0.08" sweep="0" dihedral="0" camber="0.01" incidence="0.0">
+  <stall aoa="35" width="2" peak="1.3"/>
+  <flap0 start="0.36" end="0.63" lift="1.5" drag="1.6"/>
+  <flap1 start="0.63" end="0.89" lift="1.05" drag="1.3"/>
   <slat start="0.42" end="0.89" aoa="3" drag="1.1"/>
--->
+
+<!-- Shortened wing that starts outboard of the engine intakes
  <wing x="-2.00" y="2.40" z="0.25" length="4.2" chord="8.1"
       taper="0.19" sweep="0" dihedral="0" camber="0.0" incidence="0.0">
-  <stall aoa="35" width="3" peak="1.3"/>
-  <flap0 start="0.0" end="0.42" lift="1.5" drag="1.5"/>
-  <flap1 start="0.42" end="0.833" lift="1.1" drag="1.3"/>
+  <stall aoa="35" width="2" peak="1.3"/>
+  <flap0 start="0.0" end="0.42" lift="1.5" drag="1.6"/>
+  <flap1 start="0.42" end="0.833" lift="1.05" drag="1.3"/>
   <slat start="0.14" end="0.833" aoa="3" drag="1.1"/>
+-->
   <control-input axis="/controls/flight/flaps" control="FLAP0"/>
   <control-input axis="/controls/flight/aileron" control="FLAP1" split="true"/>
   <control-input axis="/controls/flight/aileron-trim" control="FLAP1" split="true"/>
   <control-input axis="/controls/flight/slats" control="SLAT"/>
 
-  <control-output control="FLAP0" prop="/surface-positions/flap-pos-norm"/>
+  <control-input axis="/controls/flight/rudder" control="FLAP1" split="true" square="false"/>
+
+  <control-output control="FLAP0" prop="/surface-positions/left-flap-pos-norm"/>
+  <control-output control="FLAP0" prop="/surface-positions/right-flap-pos-norm"/>
+
   <control-output control="FLAP1" side="left"
   		prop="/surface-positions/left-aileron-pos-norm"/>
   <control-output control="FLAP1" side="right"
@@ -92,23 +93,27 @@
  </wing>
 
  <hstab x="-8.70" y="2.40" z="0.36" length="3.30" chord="5.10"
-       taper="0.11" sweep="0" dihedral="40" camber="0.0" effectiveness="1">
-  <stall aoa="24" width="7" peak="1.3"/>
-  <flap0 start="0" end="1" lift="1.4" drag="1.5"/>
+       taper="0.11" sweep="0" dihedral="40" camber="0.01" effectiveness="1">
+  <stall aoa="24" width="2" peak="1.3"/>
+  <flap0 start="0" end="1" lift="1.8" drag="1.6"/>
 
   <control-input axis="/controls/flight/elevator" control="FLAP0"/>
   <control-input axis="/controls/flight/elevator-trim" control="FLAP0"/>
 
-  <control-output control="FLAP0" prop="/surface-positions/elevator-pos-norm"/>
+  <control-input axis="/controls/flight/rudder" control="FLAP0" split="true" square="false"/>
+
+  <control-output control="FLAP0" side="left" prop="/surface-positions/left-elevator-pos-norm"/>
+  <control-output control="FLAP0" side="right" prop="/surface-positions/right-elevator-pos-norm"/>
+
   <control-speed control="FLAP0" transition-time="0.5"/>
+
  </hstab>
 
 <!-- The only figures I've found for the F119-PW-100L give 35000lb
      'class' with afterburner.  The difference between the top speed
      with and with out afterburner (mach 1.43 vs mach 2) suggests that
      the afterburner ratio is << 2:1 so I've used a ratio suggested by
-     those mach speeds + plus a fudge factor = 0.7.  Also, the engine has
-     thrust vectoring but I've not worked that out yet.
+     those mach speeds + plus a fudge factor = 0.7.
 -->
  <jet x="-6.26" y="1.20" z="0.60" mass="3000" thrust="24500" afterburner="35000">
   <control-input axis="/controls/engines/engine[0]/throttle" control="THROTTLE"/>
@@ -152,7 +157,7 @@
   <control-output control="EXTEND" prop="/canopy/position-norm"/>
  </gear>
 
-<!-- The locations and capcities are GW. -->
+<!-- The locations and capcities are guesswork. -->
 <!-- Fuselage tank -->
  <tank x="1.5" y="0" z="0.68" jet="true" capacity="8000"/>
 <!-- Left wing tank -->
@@ -170,6 +175,6 @@
  <ballast x="5.8" y="0" z="0.6" mass="200"/>
 
 <!-- Trim ballast -->
- <ballast x="6" y="0" z="0.0" mass="1000"/>
+ <ballast x="6" y="0" z="0.0" mass="2000"/>
 
 </airplane>
diff --git a/Aircraft/yf23-yasim-set.xml b/Aircraft/yf23-yasim-set.xml
index 8cb90b6ec..ff1fbad62 100755
--- a/Aircraft/yf23-yasim-set.xml
+++ b/Aircraft/yf23-yasim-set.xml
@@ -50,7 +50,7 @@ NR/MD YF23 simulation config.
 
  </sim>
 
- <controls>
+<!-- <controls>
   <engines>
    <engine n="0">
     <magnetos>3</magnetos>
@@ -60,7 +60,7 @@ NR/MD YF23 simulation config.
    </engine>
   </engines>
  </controls>
-
+-->
  <autopilot>
    <config>
 
@@ -70,15 +70,15 @@ NR/MD YF23 simulation config.
      <target-climb-rate-fpm type="float">20000.0</target-climb-rate-fpm>
      <target-descent-rate-fpm type="float">12000.0</target-descent-rate-fpm>
 
-     <elevator-adj-factor type="float">130.0</elevator-adj-factor>
+     <elevator-adj-factor type="float">500.0</elevator-adj-factor>
 
      <integral-contribution type="float">0.005</integral-contribution>
 
-     <max-aileron type="float">0.5</max-aileron>
+     <max-aileron type="float">0.6</max-aileron>
      <max-roll-deg type="float">60.0</max-roll-deg>
 
-     <roll-out-deg type="float">10.0</roll-out-deg>
-     <roll-out-smooth-deg type="float">20.0</roll-out-smooth-deg>
+     <roll-out-deg type="float">7.0</roll-out-deg>
+     <roll-out-smooth-deg type="float">15.0</roll-out-smooth-deg>
 
      <zero-pitch-throttle type="float">0.5</zero-pitch-throttle>
      <zero-pitch-trim-full-throttle type="float">0.001</zero-pitch-trim-full-throttle>