The airspeed indicator shows Indicated Airspeed IAS. The mustang stalls at around 95 mph IAS. This will occur at ANY Altitude. The airspeed indicator measures the amount of air molecules entering the pitot tube, so the amount of air passing over the wing at 500feet or 25,000 feet is exactly the same at any given Indicated airspeed. The true airspeed and groundspeed is definitely higher at altitude but the pilot is reading IAS. The mustang will drop its left wing in a stall due to the propeller wash hitting the left side of the vertical stabilizer and rudder, causing a decrease in speed of the left wing as compared to the right and stalling the left wing first, causing an incipient stall. All the pilot has to do however is push the stick forward to unload the wings and push right rudder----not right aileron. During a stall, keeping the ball of the needle and ball instrument centered will prevent a spin. In CFS however one can select an unrealistic realism setting that makes the planes stall and spin sooner and easier than in real life. The real mustang is quite predictable in its stall characteristics and is a very honest airplane.