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flightgear/src/FDM/YASim
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Colin Douglas Howell 54f954fd02 Fix for issue 1463 (YASim underestimates off-axis aerodynamic forces on fuselages) 
Change the drag coefficient for fuselages along the Y and Z axes
(i.e. perpendicular to the fuselage's main axis) to use a fixed
value of 0.5. (The value can still be adjusted using the fuselage's
"cy" and "cz" XML attributes.)

For the Y-axis and Z-axis drag on fuselages, YASim originally used
a drag coefficient equal to:

	(solver drag factor) * (fuselage length/width ratio)

This value turns out to be way too small for well-streamlined
aircraft, even those with long, narrow fuselages, and especially
so for those with short, stubby fuselages. Such fuselages are
streamlined in the X direction, but not along Y or Z.

0.5 is only a ballpark estimate, but it's reasonably close for the
common case of a fairly long fuselage with a round cross section. For
flat-sided fuselages, a larger value should be used, up to a maximum
of 2 for a slab-sided block. For short fuselages, the value should be
reduced to account for end effects. The fuselage's "cy" and "cz" XML
attributes can be modified to make such adjustments.

This fix won't affect straight flight much, but it should have a strong
impact on some maneuvers. For example, it will make slips more
effective and may make knife-edge flight easier on aerobatic aircraft
which should be capable of it.

Only aircraft which specify version="YASIM_VERSION_32" or newer are
affected.
2014-05-12 19:07:10 -07:00
..
.gitignore update gitignore 2013-02-28 13:37:49 +01:00
Airplane.cpp Fix for issue 1463 (YASim underestimates off-axis aerodynamic forces on fuselages) 2014-05-12 19:07:10 -07:00
Airplane.hpp Separate fuselage drag adjustment from that for landing gear and external weights. 2014-05-12 14:29:48 -07:00
Atmosphere.cpp Ron Jensen: extend atmosphere tables to match environment data 2007-09-05 02:01:57 +00:00
Atmosphere.hpp
BodyEnvironment.hpp Remove warnings 2009-01-04 00:00:02 +01:00
CMakeLists.txt YASim: implement a versioning system 2014-04-20 20:58:12 +02:00
ControlMap.cpp Compile with MSVC 9 2012-03-25 14:39:24 +02:00
ControlMap.hpp From Vivian: add a tunable launchbar acceleration, to better support some 2009-05-02 00:44:22 +02:00
Engine.hpp Fix a few warnings while I'm in there. Melchior poitned out that my default 2006-08-08 18:23:20 +00:00
FGFDM.cpp Fix for issue 1394 (YASim's geometry for non-cylindrical fuselages is wrong) 2014-05-06 10:38:48 +02:00
FGFDM.hpp YASim: implement a versioning system 2014-04-20 20:58:12 +02:00
FGGround.cpp Push SGMaterial use into these classes that need it. 2012-08-29 06:29:29 +02:00
FGGround.hpp Push SGMaterial use into these classes that need it. 2012-08-29 06:29:29 +02:00
Gear.cpp Push SGMaterial use into these classes that need it. 2012-08-29 06:29:29 +02:00
Gear.hpp Push SGMaterial use into these classes that need it. 2012-08-29 06:29:29 +02:00
Glue.cpp Curt noticed a while back that YASim was producing alpha and sideslip 2006-08-28 17:24:34 +00:00
Glue.hpp Curt noticed a while back that YASim was producing alpha and sideslip 2006-08-28 17:24:34 +00:00
Ground.cpp Push SGMaterial use into these classes that need it. 2012-08-29 06:29:29 +02:00
Ground.hpp Push SGMaterial use into these classes that need it. 2012-08-29 06:29:29 +02:00
Hitch.cpp Compile with MSVC 9 2012-03-25 14:39:24 +02:00
Hitch.hpp Fix some warnings identified by Clang 2013-11-16 09:41:33 +00:00
Hook.cpp Fixes a bugs in the handling of the holdback mount point (by Mathias), 2006-03-01 22:59:58 +00:00
Hook.hpp Small gcc-4.1 patch. 2006-03-18 13:10:59 +00:00
Integrator.cpp Melchior FRANZ: 2004-10-07 20:34:56 +00:00
Integrator.hpp
Jet.cpp Melchior sent me a property dump of the YF-23 in the wacky superthrust 2006-08-08 14:19:15 +00:00
Jet.hpp Add a *really* crude model of ITT, Oil Temp, and Oil Pressure. This 2004-11-23 21:35:30 +00:00
Launchbar.cpp From Vivian: add a tunable launchbar acceleration, to better support some 2009-05-02 00:44:22 +02:00
Launchbar.hpp From Vivian: add a tunable launchbar acceleration, to better support some 2009-05-02 00:44:22 +02:00
Math.hpp YASim performance optimization 2012-04-05 21:02:09 +02:00
Model.cpp Push SGMaterial use into these classes that need it. 2012-08-29 06:29:29 +02:00
Model.hpp Maik JUSTUS: (OK'ed by Andy) 2007-01-17 20:42:39 +00:00
PistonEngine.cpp "min throttle" tunable from Maik: 2009-02-27 23:42:33 +01:00
PistonEngine.hpp "min throttle" tunable from Maik: 2009-02-27 23:42:33 +01:00
Propeller.cpp Allow YASim flight models to override the hard-coded fine and coarse 2006-02-26 16:46:51 +00:00
Propeller.hpp Allow YASim flight models to override the hard-coded fine and coarse 2006-02-26 16:46:51 +00:00
PropEngine.cpp Inspired by a patch from Vivian, this adds a settable "WASTEGATE" 2006-02-27 23:35:02 +00:00
PropEngine.hpp Support for a new "contra" attribute on propellers, which properly 2004-12-13 23:48:43 +00:00
proptest.cpp Alexis Bory: 2012-11-08 09:06:24 +00:00
RigidBody.cpp Missed changed file somehow, oops. 2007-01-10 19:04:59 +00:00
RigidBody.hpp Patch from Joacim to export the inertia tensor from the command line solver. 2007-01-10 18:58:50 +00:00
Rotor.cpp Fix for CVE-2012-2091: 2013-09-14 17:39:49 +01:00
Rotor.hpp Casaba Halász: Fix some const warnings. 2009-03-05 10:52:03 +01:00
Rotorpart.cpp Remove unused variables (moment/ias) 2012-04-05 21:02:09 +02:00
Rotorpart.hpp Fix cmpiler warning. 2009-03-18 08:00:08 +01:00
SimpleJet.cpp
SimpleJet.hpp
Surface.cpp Fix for issue 1463 (YASim underestimates off-axis aerodynamic forces on fuselages) 2014-05-12 19:07:10 -07:00
Surface.hpp Fix for issue 1463 (YASim underestimates off-axis aerodynamic forces on fuselages) 2014-05-12 19:07:10 -07:00
Thruster.cpp Allow negative thrust. This allows a single recoil or vibration 2008-12-04 18:47:49 +00:00
Thruster.hpp Refactoring in preparation to add a turbine engine to YASim. The 2004-04-30 19:06:29 +00:00
TurbineEngine.cpp Oops again -- forgot that the solver needs fuel too. :) 2005-11-11 18:02:16 +00:00
TurbineEngine.hpp Fix some warnings identified by Clang 2013-11-16 09:41:33 +00:00
Turbulence.cpp Fix a problem with the YASim turbulence model. This change has been 2011-05-05 14:13:18 -05:00
Turbulence.hpp
Vector.hpp Performance optimization: empty() instead of size()>0 2013-08-19 09:02:06 +01:00
Version.cpp YASim: implement a versioning system 2014-04-20 20:58:12 +02:00
Version.hpp YASim: implement a versioning system 2014-04-20 20:58:12 +02:00
Wing.cpp YASim: implement a versioning system 2014-04-20 20:58:12 +02:00
Wing.hpp YASim: implement a versioning system 2014-04-20 20:58:12 +02:00
yasim-test.cpp Synchronized FG with the removal of 'using std::*' in simgear's easyxml 2013-11-14 22:07:50 +00:00
YASim.cxx Synchronized FG with the removal of 'using std::*' in simgear's easyxml 2013-11-14 22:07:50 +00:00
YASim.hxx Synchronized FG with the removal of 'using std::*' in simgear's easyxml 2013-11-14 22:07:50 +00:00