diff --git a/ArduCopter/config.h b/ArduCopter/config.h
index f5d92032ad..d153159918 100644
--- a/ArduCopter/config.h
+++ b/ArduCopter/config.h
@@ -232,7 +232,7 @@
 #endif
 
 #ifndef SONAR_GAIN_DEFAULT
- # define SONAR_GAIN_DEFAULT 2.0            // gain for controlling how quickly sonar range adjusts target altitude (lower means slower reaction)
+ # define SONAR_GAIN_DEFAULT 0.8            // gain for controlling how quickly sonar range adjusts target altitude (lower means slower reaction)
 #endif
 
 #ifndef THR_SURFACE_TRACKING_VELZ_MAX