From e4142d94d4d87b3504d5e58db6936c5ff70d3466 Mon Sep 17 00:00:00 2001
From: andy <andy>
Date: Tue, 22 Mar 2005 18:17:08 +0000
Subject: [PATCH] I fixed the gear-ratio handling in the solution computations
 a while back, but forgot to put the same fix into the runtime code.  Also
 added some comments so I don't get confused again the next time I come
 through here. :)

---
 src/FDM/YASim/PropEngine.cpp | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/FDM/YASim/PropEngine.cpp b/src/FDM/YASim/PropEngine.cpp
index 7930f26ca..866ef8165 100644
--- a/src/FDM/YASim/PropEngine.cpp
+++ b/src/FDM/YASim/PropEngine.cpp
@@ -125,8 +125,11 @@ void PropEngine::stabilize()
 	_eng->calc(_pressure, _temp, _omega);
         _eng->stabilize();
 
-        // Compute torque as seen by the engine's end of the
-        // gearbox.
+        // Compute torque as seen by the engine's end of the gearbox.
+        // The propeller will be moving more slowly (for gear ratios
+        // less than one), so it's torque will be higher than the
+        // engine's, so multiply by _gearRatio to get the engine-side
+        // value.
         ptau *= _gearRatio;
         float etau = _eng->getTorque();
 	float tdiff = etau - ptau;
@@ -173,6 +176,7 @@ void PropEngine::integrate(float dt)
     _eng->setFuelState(_fuel);
     
     _prop->calc(_rho, speed, _omega * _gearRatio, &thrust, &propTorque);
+    propTorque *= _gearRatio;
     _eng->calc(_pressure, _temp, _omega);
     _eng->integrate(dt);
     engTorque = _eng->getTorque();
-- 
2.39.5