Clean up curve resistance calculations

Author: SteelFill

Source/Orts.Simulation/Simulation/RollingStocks/TrainCar.cs

@@ -37,14 +37,12 @@
 using Orts.Common;
 using Orts.Formats.Msts;
 using Orts.Parsers.Msts;
-using Orts.Simulation.AIs;
 using Orts.Simulation.Physics;
 using Orts.Simulation.RollingStocks.Coupling;
 using Orts.Simulation.RollingStocks.SubSystems;
 using Orts.Simulation.RollingStocks.SubSystems.Brakes;
 using Orts.Simulation.RollingStocks.SubSystems.PowerSupplies;
 using Orts.Simulation.Signalling;
-using Orts.Simulation.Timetables;
 using ORTS.Common;
 using ORTS.Scripting.Api;
 using System;
@@ -2089,14 +2087,13 @@ public virtual void UpdateCurveForce(float elapsedClockSeconds)
                 // Base Curve Resistance (from refernce i)) = (Vehicle mass x Coeff Friction) * (Track Gauge + Vehicle Fixed Wheelbase) / (2 * curve radius)
                 // Vehicle Fixed Wheel base is the distance between the wheels, ie bogie or fixed wheels
 
-                var rBaseWagonN = 9.81f * MassKG * Train.WagonCoefficientFriction * (TrackGaugeM + RigidWheelBaseM) / (2.0f * CurrentCurveRadiusM);
+                float rBaseWagonN = GravitationalAccelerationMpS2 * MassKG * Train.WagonCoefficientFriction * (TrackGaugeM + RigidWheelBaseM) / (2.0f * CurrentCurveRadiusM);
 
                 // Speed Curve Resistance (from reference ii) - second term only) = ((Speed^2 / Curve Radius) - (Superelevation / Track Gauge) * Gravitational acceleration) * Constant
 
-                var speedConstant = 1.5f;
-                var MToMM = 1000;
-                var rspeedKgpTonne = speedConstant * Math.Abs((SpeedMpS * SpeedMpS / CurrentCurveRadiusM) - ((MToMM * SuperElevationM / MToMM * TrackGaugeM) * GravitationalAccelerationMpS2));
-                var rSpeedWagonN = GravitationalAccelerationMpS2 * (Kg.ToTonne(MassKG) * rspeedKgpTonne);
+                float speedConstant = 1.5f;
+                float rspeedKgpTonne = speedConstant * Math.Abs((SpeedMpS * SpeedMpS / CurrentCurveRadiusM) - (GravitationalAccelerationMpS2 * SuperElevationM / TrackGaugeM));
+                float rSpeedWagonN = GravitationalAccelerationMpS2 * (Kg.ToTonne(MassKG) * rspeedKgpTonne);
 
                 CurveForceN = rBaseWagonN + rSpeedWagonN;
             }