PA recently upgraded the servos that are included with the iPAs packages with better performance in mind. The NXT High Voltage servos are far superior to the Hitec servos that were previously supplied with the models. They are effectively improving the plane performance and as such we felt that its not a good idea to hold on the upgrade of the servos in the iPAs package just because of the servo bays of the models that were just produced was already cut for Hitec. Instead we supply the model with spacers that allow the user to modify the servo bay to fit the NXT servos.
In this video Shaun Vanunu, Designer of PA models is showing how these spacers should be installed