diff --git a/src/math/FGFunction.cpp b/src/math/FGFunction.cpp
index 4925b82ae..d0ac0fa33 100644
--- a/src/math/FGFunction.cpp
+++ b/src/math/FGFunction.cpp
@@ -535,7 +535,7 @@ void FGFunction::Load(Element* el, FGPropertyValue* var, FGFDMExec* fdmex,
       if (element->GetNumElements() == 1)
         Parameters.push_back(make_MathFn(round, fdmex, element, Prefix, var));
       else
-        Parameters.push_back(new aFunc<decltype(f), 2>(f, fdmex, element, Prefix, var));
+        Parameters.push_back(new aFunc<decltype(f), 1>(f, fdmex, element, Prefix, var, 2));
     } else if (operation == "atan2") {
       auto f = [](const decltype(Parameters)& p)->double {
                  return atan2(p[0]->GetValue(), p[1]->GetValue());