Definition
The two highest qualification levels of full flight simulator recognized by the FAA under 14 CFR Part 60. Both levels feature a full-size enclosed cockpit, a six-axis motion platform, and a wide field-of-view visual system, along with validated aerodynamic and systems modeling for a specific aircraft type. Level D is the highest level and adds higher-fidelity motion cueing, daylight visuals, and more rigorously validated flight dynamics, allowing it to be approved for zero-flight-time training and checking. Level C meets nearly the same standards but with slightly reduced fidelity in certain visual and motion requirements.
Plain English
These are the two top grades of flight simulator. They are full-size cockpits that move on hydraulic legs, with realistic outside views and accurate flight behavior for a specific aircraft. Level D is the most realistic of all simulators; Level C is just below it. Both are good enough that airlines can train pilots in them without ever flying the actual aircraft first.
Context Anchor
Seen in discussions of flight simulation training devices used for upset prevention and recovery training.
Derivation
The lettering comes from FAA Part 60, which sorts full flight simulators into four grades — Level A, B, C, and D — with each step up requiring better fidelity. 'FFS' simply distinguishes a full motion-platform simulator from lower-fidelity training devices like FTDs (Flight Training Devices) or ATDs (Aviation Training Devices).
Why Pilots Care
These simulators let pilots rehearse dangerous flight conditions without risk to aircraft or crew, meeting regulatory requirements for many advanced maneuvers.
Intuition Check
“Level” does not mean the airplane is straight and level here. It means the simulator’s FAA qualification category.
Example Sentence 1
The airline's new-hire training program uses a Level D FFS, so pilots complete their entire type rating in the simulator before flying the actual aircraft with passengers.
Example Sentence 2
Level C and D FFS devices can be used for most of the upset recovery maneuvers that previously had to be practiced in flight.