diff --git a/src/ODE/sixDOF/sixDOFODE/sixDOFODE.H b/src/ODE/sixDOF/sixDOFODE/sixDOFODE.H
index adb7e93e8..f73c0a6bf 100644
--- a/src/ODE/sixDOF/sixDOFODE/sixDOFODE.H
+++ b/src/ODE/sixDOF/sixDOFODE/sixDOFODE.H
@@ -316,6 +316,13 @@ public:
                 const dimensionedVector& externalMoment
             );
 
+            //- Initialize force and moment for the first time step
+            inline void initExternalForceAndMoment
+            (
+                const dimensionedVector& externalForce,
+                const dimensionedVector& externalMoment
+            );
+
 
         // Access to motion constraints
 
diff --git a/src/ODE/sixDOF/sixDOFODE/sixDOFODEI.H b/src/ODE/sixDOF/sixDOFODE/sixDOFODEI.H
index aa5e68ee0..b358c2892 100644
--- a/src/ODE/sixDOF/sixDOFODE/sixDOFODEI.H
+++ b/src/ODE/sixDOF/sixDOFODE/sixDOFODEI.H
@@ -114,6 +114,21 @@ void Foam::sixDOFODE::setExternalForceAndMoment
 }
 
 
+void Foam::sixDOFODE::initExternalForceAndMoment
+(
+    const dimensionedVector& externalForce,
+    const dimensionedVector& externalMoment
+)
+{
+    // Initialise force and moment only for the first time step
+    if (curTimeIndex_ == -1)
+    {
+        force_ = externalForce;
+        moment_ = externalMoment;
+    }
+}
+
+
 const Foam::PtrList<Foam::translationalConstraint>&
 Foam::sixDOFODE::translationalConstraints() const
 {