diff --git a/internal_filesystem/builtin/apps/com.micropythonos.settings/assets/calibrate_imu.py b/internal_filesystem/builtin/apps/com.micropythonos.settings/assets/calibrate_imu.py
index 750fa5c3..7b9a28b7 100644
--- a/internal_filesystem/builtin/apps/com.micropythonos.settings/assets/calibrate_imu.py
+++ b/internal_filesystem/builtin/apps/com.micropythonos.settings/assets/calibrate_imu.py
@@ -29,7 +29,6 @@ class CalibrateIMUActivity(Activity):
 
     # State
     current_state = CalibrationState.READY
-    calibration_thread = None
 
     # Widgets
     title_label = None