Switch Induced Simulated Pilot Induced Oscillation (SIS PIO) is a flight test technique used to simulate conditions of test pilot gain inputs that would create a PIO. In this video, the pilot switches stick input direction every time a symbol on the HUD or visual target crosses the HUD horizon line. This FTT can also be flown in aircraft without a HUD using formation chase aircraft and a visual target on that aircraft.
Check out @FlightTestFact on Twitter for more flight test safety references, videos, and information daily.
