def METHOD_NAME(self, ac_id, msg):
    if msg.name == "ROTORCRAFT_FP":
        self.ground_gs_x[self.count_gs] = float(msg['veast'])  * 0.0000019
        self.ground_gs_y[self.count_gs] = float(msg['vnorth']) * 0.0000019
        self.last_heading = float(msg['psi']) * 0.0139882
        self.count_gs = self.count_gs + 1
        if self.count_gs >= MSG_BUFFER_SIZE:
            self.count_gs = 0
        wx.CallAfter(self.update)
    elif msg.name =="AIR_DATA":
        self.airspeed[self.count_as] = float(msg['airspeed'])
        self.heading[self.count_as] = self.last_heading * math.pi / 180.0
        self.count_as = self.count_as + 1
        if self.count_as >= MSG_BUFFER_SIZE:
            self.count_as = 0
        wx.CallAfter(self.update)