diff --git a/APMrover2/GCS_Mavlink.pde b/APMrover2/GCS_Mavlink.pde
index 67cfb399f9..a026ad68be 100644
--- a/APMrover2/GCS_Mavlink.pde
+++ b/APMrover2/GCS_Mavlink.pde
@@ -1505,9 +1505,9 @@ void GCS_MAVLINK::handleMessage(mavlink_message_t* msg)
 
             // set parameter
 
-            char key[ONBOARD_PARAM_NAME_LENGTH+1];
-            strncpy(key, (char *)packet.param_id, ONBOARD_PARAM_NAME_LENGTH);
-            key[ONBOARD_PARAM_NAME_LENGTH] = 0;
+            char key[AP_MAX_NAME_SIZE+1];
+            strncpy(key, (char *)packet.param_id, AP_MAX_NAME_SIZE);
+            key[AP_MAX_NAME_SIZE] = 0;
 
             // find the requested parameter
             vp = AP_Param::find(key, &var_type);
@@ -1793,7 +1793,7 @@ GCS_MAVLINK::queued_param_send()
     // if the parameter can be cast to float, report it here and break out of the loop
     value = vp->cast_to_float(_queued_parameter_type);
 
-    char param_name[ONBOARD_PARAM_NAME_LENGTH];
+    char param_name[AP_MAX_NAME_SIZE];
     vp->copy_name(param_name, sizeof(param_name), true);
 
     mavlink_msg_param_value_send(
diff --git a/APMrover2/defines.h b/APMrover2/defines.h
index 233cb31fe4..76ac2ba304 100644
--- a/APMrover2/defines.h
+++ b/APMrover2/defines.h
@@ -240,8 +240,6 @@ enum gcs_severity {
 
 #define MAX_WAYPOINTS  ((EEPROM_MAX_ADDR - WP_START_BYTE) / WP_SIZE) - 1 // - 1 to be safe
 
-#define ONBOARD_PARAM_NAME_LENGTH 15
-
 // convert a boolean (0 or 1) to a sign for multiplying (0 maps to 1, 1 maps to -1)
 #define BOOL_TO_SIGN(bvalue) ((bvalue)?-1:1)