diff --git a/Aircraft/747-yasim-set.xml b/Aircraft/747-yasim-set.xml
index 96b2a6401..8205a229b 100644
--- a/Aircraft/747-yasim-set.xml
+++ b/Aircraft/747-yasim-set.xml
@@ -12,6 +12,8 @@ October 23 2001 John Check, fgpanels@rockfish.net
 
 <PropertyList>
 
+ <sim>
+
   <flight-model>yasim</flight-model>
   <aero>747</aero>
   <fuel-fraction>1.0</fuel-fraction>
@@ -29,6 +31,8 @@ October 23 2001 John Check, fgpanels@rockfish.net
    <path><!-- you need to set this --></path>
   </model>
 
+ </sim>
+
 </PropertyList>
 
 
diff --git a/Aircraft/X15-set.xml b/Aircraft/X15-set.xml
index dabf1f598..dc64c1559 100644
--- a/Aircraft/X15-set.xml
+++ b/Aircraft/X15-set.xml
@@ -11,6 +11,8 @@ October 23 2001 John Check, fgpanels@rockfish.net
 -->
 
 <PropertyList>
+
+ <sim>
  
   <flight-model>jsb</flight-model>
   <aero>X15</aero>
@@ -34,6 +36,8 @@ October 23 2001 John Check, fgpanels@rockfish.net
   </model_2> 
 -->
 
+ </sim>
+
 </PropertyList>
 
 
diff --git a/Aircraft/a4-yasim-set.xml b/Aircraft/a4-yasim-set.xml
index 950c0656b..f41a48eed 100644
--- a/Aircraft/a4-yasim-set.xml
+++ b/Aircraft/a4-yasim-set.xml
@@ -11,6 +11,8 @@ October 23 2001 John Check, fgpanels@rockfish.net
 -->
 
 <PropertyList>
+
+ <sim>
   
   <flight-model>yasim</flight-model>
   <aero>a4</aero>
@@ -27,6 +29,8 @@ October 23 2001 John Check, fgpanels@rockfish.net
   <model>
    <path><!-- you need to set this --></path>
   </model>
+
+ </sim>
   
 </PropertyList>
 
diff --git a/Aircraft/c172-ifr-set.xml b/Aircraft/c172-ifr-set.xml
index 6adfe9e94..63b48ad7b 100644
--- a/Aircraft/c172-ifr-set.xml
+++ b/Aircraft/c172-ifr-set.xml
@@ -11,6 +11,8 @@ October 23 2001 John Check, fgpanels@rockfish.net
 -->
 
 <PropertyList>
+
+ <sim>
  
   <flight-model>jsb</flight-model>
   <aero>c172</aero>
@@ -27,6 +29,8 @@ October 23 2001 John Check, fgpanels@rockfish.net
   <model>
    <path>Aircraft/c172/Models/N757/n757.ac</path>
   </model>
+
+ </sim>
  
 </PropertyList>
 
diff --git a/Aircraft/c172-larcsim-set.xml b/Aircraft/c172-larcsim-set.xml
index fe0eb9e59..66d6a2baf 100644
--- a/Aircraft/c172-larcsim-set.xml
+++ b/Aircraft/c172-larcsim-set.xml
@@ -11,6 +11,8 @@ October 23 2001 John Check, fgpanels@rockfish.net
 -->
 
 <PropertyList>
+
+ <sim>
  
   <flight-model>larcsim</flight-model>
   <aero>c172</aero>
@@ -27,6 +29,8 @@ October 23 2001 John Check, fgpanels@rockfish.net
   <model>
    <path>Aircraft/c172/Models/N757/n757.ac</path>
   </model>
+
+ </sim>
  
 </PropertyList>
 
diff --git a/Aircraft/c172-set.xml b/Aircraft/c172-set.xml
index e4bfba1ba..97362e0ba 100644
--- a/Aircraft/c172-set.xml
+++ b/Aircraft/c172-set.xml
@@ -11,6 +11,8 @@ October 23 2001 John Check, fgpanels@rockfish.net
 -->
 
 <PropertyList>
+
+ <sim>
  
   <flight-model>jsb</flight-model>
   <aero>c172</aero>
@@ -27,6 +29,8 @@ October 23 2001 John Check, fgpanels@rockfish.net
   <model>
    <path>Aircraft/c172/Models/N757/n757.ac</path>
   </model>
+
+ </sim>
   
 </PropertyList>
 
diff --git a/Aircraft/c172-yasim-set.xml b/Aircraft/c172-yasim-set.xml
index 7b95fa8a2..c9b581944 100644
--- a/Aircraft/c172-yasim-set.xml
+++ b/Aircraft/c172-yasim-set.xml
@@ -11,6 +11,8 @@ October 23 2001 John Check, fgpanels@rockfish.net
 -->
 
 <PropertyList>
+
+ <sim>
  
   <flight-model>yasim</flight-model>
   <aero>c172</aero>
@@ -29,6 +31,8 @@ October 23 2001 John Check, fgpanels@rockfish.net
   <model>
    <path>Aircraft/c172/Models/N757/n757.ac</path>
   </model>
+
+ </sim>
   
 </PropertyList>
 
diff --git a/Aircraft/c310-set.xml b/Aircraft/c310-set.xml
index c5b9fa561..4a8d532be 100644
--- a/Aircraft/c310-set.xml
+++ b/Aircraft/c310-set.xml
@@ -11,6 +11,8 @@ October 23 2001 John Check, fgpanels@rockfish.net
 -->
 
 <PropertyList>
+
+ <sim>
   
   <flight-model>jsb</flight-model>
   <aero>c310</aero>
@@ -29,6 +31,8 @@ October 23 2001 John Check, fgpanels@rockfish.net
    <path>Aircraft/c310/Models/cessna310r.ac</path>
   </model> 
 
+ </sim>
+
 </PropertyList>
 
 
diff --git a/Aircraft/c310-yasim-set.xml b/Aircraft/c310-yasim-set.xml
index f2adf2855..d858f1d74 100644
--- a/Aircraft/c310-yasim-set.xml
+++ b/Aircraft/c310-yasim-set.xml
@@ -11,6 +11,8 @@ October 23 2001 John Check, fgpanels@rockfish.net
 -->
 
 <PropertyList>
+
+ <sim>
  
   <flight-model>yasim</flight-model>
   <aero>c310</aero>
@@ -30,6 +32,8 @@ October 23 2001 John Check, fgpanels@rockfish.net
    <path>Aircraft/c310/Models/cessna310r.ac</path>
   </model> 
 
+ </sim>
+
 </PropertyList>
 
 
diff --git a/Aircraft/shuttle-set.xml b/Aircraft/shuttle-set.xml
index 67d0ee509..dbb5fdf41 100644
--- a/Aircraft/shuttle-set.xml
+++ b/Aircraft/shuttle-set.xml
@@ -11,6 +11,8 @@ October 23 2001 John Check, fgpanels@rockfish.net
 -->
 
 <PropertyList>
+
+ <sim>
   
   <flight-model>jsb</flight-model>
   <aero>shuttle</aero>
@@ -27,6 +29,8 @@ October 23 2001 John Check, fgpanels@rockfish.net
   <model>
    <path><!-- you need to set this --></path>
   </model>
+
+ </sim>
  
 </PropertyList>
 
diff --git a/preferences.xml b/preferences.xml
index 5d864eebc..6c9661916 100644
--- a/preferences.xml
+++ b/preferences.xml
@@ -11,7 +11,8 @@ Started September 2000 by David Megginson, david@megginson.com
 <PropertyList>
 
  <!-- General simulation preferences -->
- <sim include="Aircraft/c172-set.xml">
+ <sim>
+  <aircraft>c172</aircraft>
   <startup>
    <xsize>800</xsize>
    <ysize>600</ysize>