diff --git a/gtsam_unstable/dynamics/SimpleHelicopter.h b/gtsam_unstable/dynamics/SimpleHelicopter.h
index b1c254a9e..88f0acdce 100644
--- a/gtsam_unstable/dynamics/SimpleHelicopter.h
+++ b/gtsam_unstable/dynamics/SimpleHelicopter.h
@@ -60,7 +60,7 @@ public:
     }
 
     if (H3) {
-      Matrix D_exphxi_xi = Pose3::dExpInv_exp(h_*xik)*h_;
+      Matrix D_exphxi_xi = Pose3::ExpmapDerivative(h_*xik)*h_;
       Matrix D_hx_xi = D_hx_gkxi * D_gkxi_exphxi * D_exphxi_xi;
       *H3 = D_hx_xi;
     }
diff --git a/gtsam_unstable/dynamics/tests/testSimpleHelicopter.cpp b/gtsam_unstable/dynamics/tests/testSimpleHelicopter.cpp
index bdc71fea2..34bcdea86 100644
--- a/gtsam_unstable/dynamics/tests/testSimpleHelicopter.cpp
+++ b/gtsam_unstable/dynamics/tests/testSimpleHelicopter.cpp
@@ -57,7 +57,7 @@ TEST(Reconstruction, ExpmapInvDeriv) {
           ),
       Vector6(Vector::Zero(6)), 1e-5
       );
-  Matrix dExpInv = Pose3::dExpInv_exp(h*V1_g1);
+  Matrix dExpInv = Pose3::ExpmapDerivative(h*V1_g1);
   EXPECT(assert_equal(numericalExpmap, dExpInv, 1e-2));
 }