message: Fixed Issue 61 (Crash on stop button)
diff: @@ -47,6 +47,8 @@ class Phantom {
  QuadXAPDynamics dynamics = QuadXAPDynamics(_params);
  + private:
  +
  Vehicle _vehicle = Vehicle(&dynamics);
  // Threaded worker for flight control
  @@ -59,6 +61,8 @@ class Phantom {
  _vehicle.addProp(index-1, x*d, y*d, +.15, mesh);
  }
  + public:
  +
  void build(APawn * pawn)
  {
  _vehicle.buildWithAudio(pawn, FrameStatics.mesh.Get());
  @@ -79,6 +83,8 @@ class Phantom {
  void BeginPlay(FFlightManager * flightManager)
  {
  + _flightManager = flightManager;
  +
  _vehicle.BeginPlay(flightManager);
  }
  