diff --git a/src/modules/commander/airspeed_calibration.cpp b/src/modules/commander/airspeed_calibration.cpp
index 598cfe9e2d..0e58c68b60 100644
--- a/src/modules/commander/airspeed_calibration.cpp
+++ b/src/modules/commander/airspeed_calibration.cpp
@@ -186,7 +186,7 @@ int do_airspeed_calibration(int mavlink_fd)
 	usleep(500 * 1000);
 
 	calibration_counter = 0;
-	const int maxcount = 3000;
+	const unsigned maxcount = 3000;
 
 	/* just take a few samples and make sure pitot tubes are not reversed, timeout after ~30 seconds */
 	while (calibration_counter < maxcount) {