RE: How to??? Flat spins??
Getting a little bit deeper into this subject, there is a difference between a flat spin and a blender which results in a flatter than normal spin which easily converts into a very flat spin. Here are my methods for all of the above.
1. Flat spin upright. Slow the airplane to a stall and enter a normal spin with full up and full rudder and aileron deflected in the same direction. After the spin develops, smoothly return your ailerons to neutral and while gently adding power, slowly move your ailerons to opposite of the rudder. This creates more drag and lift on the inside wing, raising the wing and the gyroscopic precession of the motor will raise the nose flattening out the spin. To much opposite aileron will often cause the airplane to fold out of the spin. The further back the CG, the more opposite aileron can be used resulting in even flatter spins.
2. Flat spin inverted. Fly into a stall inverted and push full down and full rudder with full opposite aileron. After the spin develops, move ailerons to neutral and, while gently adding power, move the ailerons to the same direction as rudder.
3. Blender to inverted flat spin to flatter spin. Slow the airplane to moderate speed, pull to low throttle or idle and push the nose straight down. You may add rolls or simply enter the blender without rolling. Same result, different effect aesthetically. After a short down line push as you would for an inverted spin, full down, opposite full rudder and aileron. This will result in a flat spin because of the centrifugal forces from the accelerated rotations on entry. Here, again, slowly cross the aileron and add throttle. This will further flatten the spin. On some airplanes, the correct combination of control deflection, power, and CG can arrest the descent completely as the airplane flies around in the inside wing.
It is important to realize that getting the spins perfect on any particular airplane requires finding the right combination of control throws, power settings, and CG. While the normal spin entry is simple and can normally be executed by hitting the stops, the flat portion can be either a nervous, ratchety thing or a super smooth, beautiful, tight rotation with very slow descent. Common mistakes are not using enough or too much power, CG to far forward, or getting too rough on the ailerons.
RECOVERY. Start with simple recovery. Release controls and cut power to idle, allow the airplane to start flying and gently pull or push to horizontal. Common mistakes. Not cutting power or releasing elevator which can result in a fatal spin (most modern high performance aerobats will fly right out of any type of spin with their high power ratios, but some airplanes still need recovery and I have seen quite a few crashes). Also, yanking a slow airplane with too much elevator can result in a snapping spin to mother earth. Shoud releasing the controls and not cutting power cause the rotation to arrest, then apply opposite rudder to stop the rotation. Should that not arrest the rotation push down elevator (for upright spins, eh) to lower the nose. If at that point your airplane does not recover, start planning you next airplane. Again, most airplanes will leave a spin easily and classic recovery is becoming a thing of the past for heavy, highly loaded airplanes. I do have a Pitts S-1-11B with very rear CG that will continue autorotation with neutral controls and demands opposite rudder to stop. It freaked me out the first time but I had lots of room and remembered opposite rudder.
Happy spins,
Mark