The stall turn:
The stall turn, also called a hammerhead turn, makes use of the airplane’s rudder and is a relatively simple maneuver to perform. The aim of the stall turn is to perform a vertical climb, reduce power at the top to quickly stop the climb, while simultaneously applying full rudder to rotate the plane through 180° about its CG position, or thereabouts.
How to fly it: As before, begin with a straight and level flight path. At point A in the picture above, apply full power and up elevator, putting the airplane into a vertical climb. Adjust the rudder and elevator as necessary to maintain the climb as vertically and as straight as possible, without going into the beginnings of a loop i.e. don’t keep holding in up elevator.
Let it climb for a few seconds (depending on how much power you have to hand*) and then, at point B, reduce throttle** and – here’s the important part – apply full rudder to the left or right. If the airplane doesn’t look like it’s going to turn neatly, give the throttle a small blip to get some prop wash (air movement) over the rudder.
Once the airplane has spun round through 180° and is facing the ground, return the rudder to neutral and let the airplane go naturally into a brief vertical dive for a second or so. Then, at point C, apply both motor power and up elevator to pull out of the dive and resume straight and level flying.
*How long you climb for will largely be determined by how much power you have – less powerful planes will just run out of steam after a few seconds of climbing vertically, whereas planes with unlimited power can keep on going – in which case, limit your climb to no more than three or four seconds.
**How much you reduce throttle, at the turn, depends on a few things, not least of which is the type of plane and size of rudder. You shouldn’t cut the motor right back, because you need some prop wash (i.e. airflow) over the rudder to facilitate the turn. Only experience and practice will tell you how much power you need at the turn.
Above is the stall turn on video (on the RealFlight rc flight simulator), including close-ups of the Tx stick inputs and the airplane’s response. ?? CHECK MODE ??
If you want you can use the wind direction to help you perform the stall turn by flying crosswind. Fly at 90 degrees to the wind and turn the airplane in to the wind at the top of the climb. The wind on the fin pushes the plane round for the perfect maneuver!