diff --git a/AirLib/include/api/RpcLibAdapatorsBase.hpp b/AirLib/include/api/RpcLibAdapatorsBase.hpp
index 50701270c3..96bc16ee49 100644
--- a/AirLib/include/api/RpcLibAdapatorsBase.hpp
+++ b/AirLib/include/api/RpcLibAdapatorsBase.hpp
@@ -65,7 +65,7 @@ class RpcLibAdapatorsBase {
         }
     };
     struct RotorVector {
-        RotorParameters rotor[4];
+        std::vector<RotorParameters> rotor;
 
         MSGPACK_DEFINE_MAP(rotor);
 
@@ -74,8 +74,10 @@ class RpcLibAdapatorsBase {
 
         RotorVector(const msr::airlib::RotorVector& s)
         {
-            for (unsigned int i = 0; i < 5; i++)
+            rotor.clear();
+            for (unsigned int i = 0; i < s.rotor.size(); i++)
             {
+                rotor.push_back(RotorParameters());
                 rotor[i] = s.rotor[i];
             }
         }
@@ -83,7 +85,7 @@ class RpcLibAdapatorsBase {
         msr::airlib::RotorVector to() const
         {
             msr::airlib::RotorVector d;
-            for (unsigned int i = 0; i < 5; i++)
+            for (unsigned int i = 0; i < d.rotor.size(); i++)
             {
                 d.rotor[i].speed = rotor[i].speed;
                 d.rotor[i].thrust = rotor[i].thrust;
diff --git a/AirLib/include/common/CommonStructs.hpp b/AirLib/include/common/CommonStructs.hpp
index 67978a3166..edaef49eaa 100644
--- a/AirLib/include/common/CommonStructs.hpp
+++ b/AirLib/include/common/CommonStructs.hpp
@@ -18,7 +18,7 @@ struct RotorParameters {
     {}
 };
 struct RotorVector {
-    RotorParameters rotor[4];
+    std::vector<RotorParameters> rotor;
 
     RotorVector()
     {}
diff --git a/Unreal/Plugins/AirSim/Source/Vehicles/Multirotor/MultirotorPawnSimApi.cpp b/Unreal/Plugins/AirSim/Source/Vehicles/Multirotor/MultirotorPawnSimApi.cpp
index 6ff325ba3a..7573acd121 100644
--- a/Unreal/Plugins/AirSim/Source/Vehicles/Multirotor/MultirotorPawnSimApi.cpp
+++ b/Unreal/Plugins/AirSim/Source/Vehicles/Multirotor/MultirotorPawnSimApi.cpp
@@ -72,9 +72,11 @@ void MultirotorPawnSimApi::updateRenderedState(float dt)
     collision_response = multirotor_physics_body_->getCollisionResponseInfo();
 
     //update rotor poses
+    rotor_states_.rotors.rotor.clear();
     for (unsigned int i = 0; i < rotor_count_; ++i) {
         const auto& rotor_output = multirotor_physics_body_->getRotorOutput(i);
         // update private rotor variable
+        rotor_states_.rotors.rotor.push_back(RotorParameters());
         rotor_states_.rotors.rotor[i].speed = rotor_output.speed;
         rotor_states_.rotors.rotor[i].thrust = rotor_output.thrust;
         rotor_states_.rotors.rotor[i].torque_scaler = rotor_output.torque_scaler;