When anti skid system automatically deactivated?

This may vary by aircraft size and type. The Boeing(McDonnell Douglas) MD11 anti-skid will deactivate at speeds below 12-16 knots. Due to problems with the Center Landing Gear stability, the anti-skid may be deactivated completely for some passenger configuration MD11. However, if not deactivated, such as on MD11F Freighters, the CLG may not engage at higher speeds until 30 seconds after touchdown. There is a complicated logic in the software.