diff --git a/ArduCopter/GCS_Mavlink.pde b/ArduCopter/GCS_Mavlink.pde
index a426b8267b..a86dbd4478 100644
--- a/ArduCopter/GCS_Mavlink.pde
+++ b/ArduCopter/GCS_Mavlink.pde
@@ -762,7 +762,7 @@ bool GCS_MAVLINK::try_send_message(enum ap_message id)
 const AP_Param::GroupInfo GCS_MAVLINK::var_info[] PROGMEM = {
     // @Param: RAW_SENS
     // @DisplayName: Raw sensor stream rate
-    // @Description: Raw sensor stream rate to ground station
+    // @Description: Stream rate of RAW_IMU, SCALED_IMU2, SCALED_PRESSURE, and SENSOR_OFFSETS to ground station
     // @Units: Hz
     // @Range: 0 10
     // @Increment: 1
@@ -771,7 +771,7 @@ const AP_Param::GroupInfo GCS_MAVLINK::var_info[] PROGMEM = {
 
     // @Param: EXT_STAT
     // @DisplayName: Extended status stream rate to ground station
-    // @Description: Extended status stream rate to ground station
+    // @Description: Stream rate of SYS_STATUS, MEMINFO, MISSION_CURRENT, GPS_RAW_INT, NAV_CONTROLLER_OUTPUT, and LIMITS_STATUS to ground station
     // @Units: Hz
     // @Range: 0 10
     // @Increment: 1
@@ -780,7 +780,7 @@ const AP_Param::GroupInfo GCS_MAVLINK::var_info[] PROGMEM = {
 
     // @Param: RC_CHAN
     // @DisplayName: RC Channel stream rate to ground station
-    // @Description: RC Channel stream rate to ground station
+    // @Description: Stream rate of SERVO_OUTPUT_RAW and RC_CHANNELS_RAW to ground station
     // @Units: Hz
     // @Range: 0 10
     // @Increment: 1
@@ -789,7 +789,7 @@ const AP_Param::GroupInfo GCS_MAVLINK::var_info[] PROGMEM = {
 
     // @Param: RAW_CTRL
     // @DisplayName: Raw Control stream rate to ground station
-    // @Description: Raw Control stream rate to ground station
+    // @Description: Stream rate of RC_CHANNELS_SCALED (HIL only) to ground station
     // @Units: Hz
     // @Range: 0 10
     // @Increment: 1
@@ -798,7 +798,7 @@ const AP_Param::GroupInfo GCS_MAVLINK::var_info[] PROGMEM = {
 
     // @Param: POSITION
     // @DisplayName: Position stream rate to ground station
-    // @Description: Position stream rate to ground station
+    // @Description: Stream rate of GLOBAL_POSITION_INT to ground station
     // @Units: Hz
     // @Range: 0 10
     // @Increment: 1
@@ -807,7 +807,7 @@ const AP_Param::GroupInfo GCS_MAVLINK::var_info[] PROGMEM = {
 
     // @Param: EXTRA1
     // @DisplayName: Extra data type 1 stream rate to ground station
-    // @Description: Extra data type 1 stream rate to ground station
+    // @Description: Stream rate of ATTITUDE and SIMSTATE (SITL only) to ground station
     // @Units: Hz
     // @Range: 0 10
     // @Increment: 1
@@ -816,7 +816,7 @@ const AP_Param::GroupInfo GCS_MAVLINK::var_info[] PROGMEM = {
 
     // @Param: EXTRA2
     // @DisplayName: Extra data type 2 stream rate to ground station
-    // @Description: Extra data type 2 stream rate to ground station
+    // @Description: Stream rate of VFR_HUD to ground station
     // @Units: Hz
     // @Range: 0 10
     // @Increment: 1
@@ -825,7 +825,7 @@ const AP_Param::GroupInfo GCS_MAVLINK::var_info[] PROGMEM = {
 
     // @Param: EXTRA3
     // @DisplayName: Extra data type 3 stream rate to ground station
-    // @Description: Extra data type 3 stream rate to ground station
+    // @Description: Stream rate of AHRS, HWSTATUS, and SYSTEM_TIME to ground station
     // @Units: Hz
     // @Range: 0 10
     // @Increment: 1
@@ -834,7 +834,7 @@ const AP_Param::GroupInfo GCS_MAVLINK::var_info[] PROGMEM = {
 
     // @Param: PARAMS
     // @DisplayName: Parameter stream rate to ground station
-    // @Description: Parameter stream rate to ground station
+    // @Description: Stream rate of PARAM_VALUE to ground station
     // @Units: Hz
     // @Range: 0 10
     // @Increment: 1