Among ekf tuning parameters, there is ekf drag specific forces.
Developer documents tell me bit position 4 of EKF2_AID_MASK set true,
but in QGroundControl(version 3.2.0) parameter setting, that position means vision yaw fusion enable.
What is wrong? document? or qgroundcontrol?
Even if I didn't review ekf source code, I guess Drag Specific Forces related to this kind of research. [Martin, The true Role of Accelerometer Feedback in Quadrotor Control, 2009]