diff --git a/README.md b/README.md
index 8bd4ff7..7875851 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,9 @@
 # qtrocket
 Model Rocket Simulator written in C++ and Qt Toolkit
+
+QtRocket is still in the very early stages of development, and not suitable for any real use. It currently calculates the trajectory of a cannonball with the effects of air resistance. Some of the basic architecture is coming together, but the current implementation is only mature enough to create a cannonball and launch it.
+
+This is also an experiment and learning platform for me to learn Qt GUI programming, so if it is non-standard or very strange to experienced Qt programmers, that's why.
+
+Another feature is the use of ANSI standard C++17 for the bulk of the application. Qt specific features are limited to the GUI.
+
diff --git a/sim/Propagator.cpp b/sim/Propagator.cpp
index 6389d33..7d33d33 100644
--- a/sim/Propagator.cpp
+++ b/sim/Propagator.cpp
@@ -59,7 +59,7 @@ void Propagator::runUntilTerminate()
       }
       */
 
-      std::swap(currentState, nextState);
+      std::swap(currentState, tempRes);
       if(saveStates)
       {
          states.push_back(currentState);