Summary
We propose to adopt a new airworthiness directive (AD) for certain Dassault Aviation Model MYSTERE-FALCON 900 airplanes, FALCON 900EX airplanes, and FALCON 2000EX airplanes. This proposed AD was prompted by a report that during a test flight, it was found that the yaw damper on the takeoff roll can increase the Minimum Control Speed on Ground (Vmcg). This proposed AD would require revising the airplane flight manual to incorporate procedures for the flightcrew to check that the yaw damper is set to off before takeoff. We are proposing this AD to ensure that the flightcrew has procedures to set the yaw damper to ``off'' before takeoff, which, if activated, could result in reduced control of the airplane if one engine were to fail during takeoff.