It would be prohibitively expensive to do this in flight test. Using simulation, hundreds of stops can be made in a day. Tuning parameters can be quickly adjusted and tested through a range of conditions. Conditions that are unsafe to test on the airplane can be tested in simulation. Troubleshooting It is sometimes possible to fix a problem without understanding it, through extensive trial and error, but it is much easier with understanding.
Simulation is a great tool for understanding.
To reproduce real world behavior in a simulation, the physics of the situation must be understood well enough to write equations that are an analog to the real world. Nowhere is it as easy to see and understand the inner workings of brake control than it is in simulation. Flight testing alone cannot provide the depth of understanding that simulation does. No other company in the world has conducted braking simulations of as many different types of aircraft as has Hydro-Aire. No other company has the experience to recognize and then quickly simulate as many different types of aircraft behaviors as does Hydro-Aire.