diff --git a/Tools/autotest/arducopter.py b/Tools/autotest/arducopter.py
index abe9d075cd..abd1787784 100644
--- a/Tools/autotest/arducopter.py
+++ b/Tools/autotest/arducopter.py
@@ -122,7 +122,7 @@ class AutoTestCopter(AutoTest):
     def set_autodisarm_delay(self, delay):
         self.set_parameter("DISARM_DELAY", delay)
 
-    def user_takeoff(self, alt_min=30):
+    def user_takeoff(self, alt_min=30, timeout=30, max_err=5):
         '''takeoff using mavlink takeoff command'''
         self.run_cmd(mavutil.mavlink.MAV_CMD_NAV_TAKEOFF,
                      0, # param1
@@ -133,15 +133,15 @@ class AutoTestCopter(AutoTest):
                      0, # param6
                      alt_min # param7
                      )
-        self.progress("Ran command")
-        self.wait_for_alt(alt_min)
+        self.wait_for_alt(alt_min, timeout=timeout, max_err=max_err)
 
     def takeoff(self,
                 alt_min=30,
                 takeoff_throttle=1700,
                 require_absolute=True,
                 mode="STABILIZE",
-                timeout=120):
+                timeout=120,
+                max_err=5):
         """Takeoff get to 30m altitude."""
         self.progress("TAKEOFF")
         self.change_mode(mode)
@@ -150,10 +150,10 @@ class AutoTestCopter(AutoTest):
             self.zero_throttle()
             self.arm_vehicle()
         if mode == 'GUIDED':
-            self.user_takeoff(alt_min=alt_min)
+            self.user_takeoff(alt_min=alt_min, timeout=timeout, max_err=max_err)
         else:
             self.set_rc(3, takeoff_throttle)
-        self.wait_for_alt(alt_min=alt_min, timeout=timeout)
+        self.wait_for_alt(alt_min=alt_min, timeout=timeout, max_err=max_err)
         self.hover()
         self.progress("TAKEOFF COMPLETE")
 
@@ -202,7 +202,7 @@ class AutoTestCopter(AutoTest):
             3: 1000,
             4: 1500,
         })
-        self.takeoff(alt_min=dAlt)
+        self.takeoff(alt_min=dAlt, mode='GUIDED')
         self.change_mode("ALT_HOLD")
 
         self.progress("Yaw to east")
@@ -905,6 +905,7 @@ class AutoTestCopter(AutoTest):
             self.test_battery_failsafe(timeout=timeout)
         except Exception as e:
             self.print_exception_caught(e)
+            self.disarm_vehicle(force=True)
             ex = e
 
         self.set_parameter('BATT_LOW_VOLT', 0)
@@ -6573,6 +6574,37 @@ class AutoTestCopter(AutoTest):
             self.reboot_sitl()
             self.fly_rangefinder_drivers_fly([x[0] for x in do_drivers])
 
+    def fly_rangefinder_drivers_maxalt(self):
+        '''test max-height behaviour'''
+        # lightwareserial goes to 130m when out of range
+        self.set_parameters({
+            "SERIAL4_PROTOCOL": 9,
+            "RNGFND1_TYPE": 8,
+            "WPNAV_SPEED_UP": 1000,  # cm/s
+        })
+        self.customise_SITL_commandline([
+            "--uartE=sim:lightwareserial",
+        ])
+        self.takeoff(95, mode='GUIDED', timeout=240, max_err=0.5)
+        self.assert_rangefinder_distance_between(90, 100)
+
+        self.wait_rangefinder_distance(90, 100)
+
+        rf_bit = mavutil.mavlink.MAV_SYS_STATUS_SENSOR_LASER_POSITION
+
+        self.assert_sensor_state(rf_bit, present=True, enabled=True, healthy=True)
+        self.assert_distance_sensor_quality(100)
+
+        self.progress("Moving higher to be out of max rangefinder range")
+        self.fly_guided_move_local(0, 0, 150)
+
+        # sensor remains healthy even out-of-range
+        self.assert_sensor_state(rf_bit, present=True, enabled=True, healthy=True)
+
+        self.assert_distance_sensor_quality(1)
+
+        self.do_RTL()
+
     def fly_ship_takeoff(self):
         # test ship takeoff
         self.wait_groundspeed(0, 2)
@@ -7838,6 +7870,10 @@ class AutoTestCopter(AutoTest):
              "Test rangefinder drivers",
              self.fly_rangefinder_drivers),  # 62s
 
+            ("RangeFinderDriversMaxAlt",
+             "Test rangefinder drivers - test max alt",
+             self.fly_rangefinder_drivers_maxalt),  # 25s
+
             ("MaxBotixI2CXL",
              "Test maxbotix rangefinder drivers",
              self.fly_rangefinder_driver_maxbotix),  # 62s
diff --git a/Tools/autotest/common.py b/Tools/autotest/common.py
index 37c5b5bde2..bcb3349c08 100644
--- a/Tools/autotest/common.py
+++ b/Tools/autotest/common.py
@@ -5206,6 +5206,51 @@ class AutoTest(ABC):
             return msg.relative_alt / 1000.0  # mm -> m
         return msg.alt / 1000.0  # mm -> m
 
+    def assert_rangefinder_distance_between(self, dist_min, dist_max):
+        m = self.assert_receive_message('RANGEFINDER')
+
+        if m.distance < dist_min:
+            raise NotAchievedException("below min height (%f < %f)" %
+                                       (m.distance, dist_min))
+
+        if m.distance > dist_max:
+            raise NotAchievedException("above max height (%f > %f)" %
+                                       (m.distance, dist_max))
+
+    def assert_distance_sensor_quality(self, quality):
+        m = self.assert_receive_message('DISTANCE_SENSOR')
+
+        if m.signal_quality != quality:
+            raise NotAchievedException("Unexpected quality; want=%f got=%f" %
+                                       (quality, m.signal_quality))
+
+    def get_rangefinder_distance(self):
+        m = self.mav.recv_match(type='RANGEFINDER',
+                                blocking=True,
+                                timeout=5)
+        if m is None:
+            raise NotAchievedException("Did not get RANGEFINDER message")
+
+        return m.distance
+
+    def wait_rangefinder_distance(self, dist_min, dist_max, timeout=30, **kwargs):
+        '''wait for RANGEFINDER distance'''
+        def validator(value2, target2=None):
+            if dist_min <= value2 <= dist_max:
+                return True
+            else:
+                return False
+
+        self.wait_and_maintain(
+            value_name="RageFinderDistance",
+            target=dist_min,
+            current_value_getter=lambda: self.get_rangefinder_distance(),
+            accuracy=(dist_max - dist_min),
+            validator=lambda value2, target2: validator(value2, target2),
+            timeout=timeout,
+            **kwargs
+        )
+
     def get_esc_rpm(self, esc):
         if esc > 4:
             raise ValueError("Only does 1-4")