Adjusted least squares means of the laboratory-racetrack difference in TTD dynamic surface properties for each main effect surface, impact velocity [m/s, meter per second], impact angle [°, degree]) averaged over all other factors, and reported as a percentage of the overall racetrack average for that variable.

<p>For each main effect, a P<0.05 means the magnitude of the laboratory-racetrack difference changed significantly when the level of that main effect changed.</p>