def cmd_takeoff(self, args):
        '''take off'''
        if ( len(args) != 1):
            print("Usage: takeoff ALTITUDE_IN_METERS")
            return

        if (len(args) == 1):
            altitude = float(args[0])
            print("Take Off started")
            self.master.mav.command_long_send(
                self.settings.target_system,  # target_system
                mavutil.mavlink.MAV_COMP_ID_SYSTEM_CONTROL, # target_component
                mavutil.mavlink.MAV_CMD_NAV_TAKEOFF, # command
                0, # confirmation
                0, # param1
                0, # param2
                0, # param3
                0, # param4
                0, # param5
                0, # param6
                altitude)
take off