Новые "фишки" DCS World версии 1.5.5⁠⁠

https://ru.wikipedia.org/wiki/Digital_Combat_Simulator

Если кратко, - то тем же, чем отличается Жигули от Мерседеса.

Вот тут кроются основные отличия

Aerodynamic flight models

There are four aerodynamic flight models used in DCS World:

Standard Flight Model (SFM) – A data driven flight model, with some pre-defined scripting for some complex aerodynamic events. The only aircraft available to be flown by the player that have a Standard Flight Model are the Su-33, and all three variants of the MiG-29; however, Eagle Dynamics is in the process of updating the two.[10][11]

Advanced Flight Model (AFM/AFM+) – Airflow and edge of envelope simulation, using multiple points of force application and calculation on the relevant flight surfaces. Scripting of complex events is not used. An augmented AFM+ model which includes limited modelling of the fuel and hydraulic system weighting is also included in some aircraft (Su-25 and A-10A).

Professional Flight Model (PFM) – An expansion of the AFM, this level of modelling includes data from complex model wind tunnel simulation, a much more detailed and dynamic aircraft model (for example taking into consideration deployed or retracted landing gear, and the effects of deploying them in flight), complex simulation of control surface movements, complex simulation of autopilot actions, and the effects of fluid movements (fuel and hydraulic) on flight dynamics. This level of modelling also includes actual real world aircraft test data, where possible.

External Flight Model (EFM) – A subset of the PFM, made available for third party developers, it essentially defines all external forces from the PFM, but allows the developers to calculate and apply internal forces (fluid movements, control surfaces, etc.) within their own model.

System models

There are two levels of system modelling in DCS World:

Standard Systems Modeling (SSM): Only cockpit system essential for flight, navigation, and combat are directly simulated – although the range of systems needed for these can be quite broad. Player control is limited to keyboard, mouse, and joystick/HOTAS controls.

Advanced Systems Modeling (ASM): Most cockpit systems are carefully modeled, even if they are not directly related to flight, navigation, or combat. Almost all cockpit controls are functional, allowing the player/pilot to interact with them using mouse or touchscreen. This means that for the most part, the aircraft can be controlled via on screen controls and the joystick/HOTAS controls, although keyboard controls are still an option.

Cockpit models

3DoF (3 degrees of freedom): A fully simulated three dimensional model of the cockpit, which the player/pilot can rotate the camera to "look around", and control the level of camera zoom. Head tracking hardware – such as TrackIR is supported. There are no longer any models using 3DoF as of October 2015, under the new 1.5 update.

6DoF (Six degrees of freedom): A fully simulated three dimensional model of the cockpit is presented, which the player can not only "look around", but move the camera/head freely in three dimensional space. Combined with head tracking hardware, this allows player/pilots to "lean around" the flight stick to see controls on the panel in front of them, crane their head to look over the dash, or turn around and lean around the seat to look behind the plane in flight.