From 0970aead3274a892ff8979d9bc91f185c99634bc Mon Sep 17 00:00:00 2001
From: ehofman <ehofman>
Date: Sun, 7 Nov 2004 14:50:01 +0000
Subject: [PATCH] David Culp:

Here are files to get automated contrails working.  I've set up contrails for
the 737, using my simple, untextured contrail model.  Vivian has made another
contrail model, but I'm still trying to get his to work.  I'm hoping others
will try to make contrail models also.

Here's some code that defines a top to thermals.  When the top of a thermal is
reached the strength is phased-out linearly over the next 100 feet of
altitude.  At first I tried just capping the thermal at the top, but the
change in thermal strength was too fast for the FDM to handle well.

Included is a new version of the thermal scenario that includes a top
(height-msl) to the thermal.  The default value is 5000 feet.
---
 Data/AI/thermal_demo.xml | 5 +++--
 preferences.xml          | 1 +
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/Data/AI/thermal_demo.xml b/Data/AI/thermal_demo.xml
index 99f6d613e..47dddab3d 100644
--- a/Data/AI/thermal_demo.xml
+++ b/Data/AI/thermal_demo.xml
@@ -9,8 +9,9 @@
    <type>thermal</type>
    <latitude>37.61633</latitude>
    <longitude>-122.38334</longitude>
-   <strength-fps>8.33</strength-fps>
-   <diameter-ft>4000.0</diameter-ft>
+   <strength-fps>13.49</strength-fps>
+   <diameter-ft>4800.0</diameter-ft>
+   <height-msl>5000</height-msl>
   </entry>
 
  </scenario>
diff --git a/preferences.xml b/preferences.xml
index 7e90b6f66..60cac847f 100644
--- a/preferences.xml
+++ b/preferences.xml
@@ -441,6 +441,7 @@ Started September 2000 by David Megginson, david@megginson.com
   <params>
    <real-world-weather-fetch type="bool">false</real-world-weather-fetch>
    <control-fdm-atmosphere type="bool">false</control-fdm-atmosphere>
+   <contrail-altitude>30000</contrail-altitude>
   </params>
 
  </environment>