rudder problem solved
Add this entry in your data.ini under fuselage.
[Fuselage]
ModelNodeName=Fuselage
ShowFromCockpit=FALSE
DamageRating=DESTROYED
MassFraction=0.380
HasAeroCoefficients=TRUE
LiftSurface=TRUE
CL0= 0.0325
CLa= 0.0050
CD0= 0.0055
Cmq=-0.5738
Cmad=-0.4760
Cyb=-0.3484
CLaMachTableNumData=4
CLaMachTableDeltaX=0.15
CLaMachTableStartX=0.00
CLaMachTableData=1.115,1.125,0.75,0.50
CD0MachTableNumData=3
CD0MachTableDeltaX=0.40
CD0MachTableStartX=0.00
CD0MachTableData=0.915,0.975,5.80
CmqMachTableNumData=3
CmqMachTableDeltaX=0.40
CmqMachTableStartX=0.00
CmqMachTableData=1.000,1.000,1.000
StructuralFactor=5.0
MinExtentPosition=-0.85,0.35,-0.05
MaxExtentPosition= 0.85,-7.5,1.00
CollisionPoint[001]=0.00,0.35,-0.05
CollisionPoint[002]=0.00,-4.00,0.00
CollisionPoint[003]=0.00,-6.00,0.05
CollisionPoint[004]=0.00,-7.50,0.85
HasVortexEmitter=FALSE
SystemName[001]=Leftgun
SystemName[002]=Rightgun
SystemName[003]=WGunnerL
SystemName[004]=WgunnerR
SystemName[005]=Pontoons
SystemName[006]=LeftMainGear
SystemName[007]=RightMainGear
SystemName[008]=TailLight
SystemName[009]=Rudder <-------------------------- ADD THIS