In reaction, he used his knowledge of particle physics to create a real-time computational fluid dynamics (CFDs) model for "Flight Unlimited". The result is a simulated atmosphere: air acts as a fluid that automatically reacts to the shape of any object placed within it. Blackley gave the example that a lawn chair, if placed within the game's real-time CFDs model, would fall merely because of its shape. The game's planes fly because the interaction of their architecture with the atmosphere creates lift, as with real-world aircraft. Changes in the plane's direction are caused by the interaction of their flight control surfaces (ailerons, elevators and rudders) with the simulated atmosphere. Because it simulates the dynamics of flight in real-time, the system allows for aerobatic maneuvers that were impossible in previous flight simulators. In 1994, Blackley said that it was possibly the first flight code designed for aerobatics. In constructing the CFDs model, Blackley and the team built from the Navier–Stokes equations of fluid motion, which Blackley described as "horrible, complicated partial differential equations". According to "Computer Gaming World", Blackley did not seek to represent the equations with perfect accuracy, and he was satisfied when the results were consistent and the sensation that they generated was correct.