diff --git a/Tools/autotest/common.py b/Tools/autotest/common.py
index 2f2a35b448..98767a7fc2 100644
--- a/Tools/autotest/common.py
+++ b/Tools/autotest/common.py
@@ -1088,6 +1088,7 @@ class AutoTest(ABC):
     def disarm_vehicle(self, timeout=60, force=False):
         """Disarm vehicle with mavlink disarm message."""
         self.progress("Disarm motors with MAVLink cmd")
+        self.drain_mav_unparsed()
         p2 = 0
         if force:
             p2 = 21196 # magic force disarm value